I'll reply to 3 first to get it out of the way, so I can focus the next few hours on 1
3. MoM had a huge spellbook of over 100 spells. and again they were not just lame "ice bolt does 10 ICE damage and fire bolt does 10 FIRE damage" stupid essentially duplicate spells. Thre were some really well thought out and different spells that just seemed to fit the school that they came from. So far, it seems like the spell selection is going to be much less deep in Elemental.
Huge spellbook only matters if it has usable spells. In MOM, some spells were either completely broken (Not working: Flying Fortress, Cloak of Fear, doing the opposite thing: Subversion, corrupting savegames: Resurrect, crashing the game: Call Lightning) or were just plain crap. (Most of Death spells - for unknown reason many games make negative enchantments require to pass a Magic Resistance check, but positive buffs which often do pretty much the same thing have no such requirement. In MOM, many races and magical creatures had high MR, making death magic spells 1) very random and unpredictable 2) very unlikely to work)
Really, think about how many MOM spells you actually used. Most people I know used few easy, time-tested strategies, like death war trolls, slingers with lionheart, 11 death books and wraiths, or paladins. Many people just used these because they were so much easier than everything else. Few liked balanced, but still decent races like Nomad or Beastmen. Even fewer played with gnolls or lizardmen. I did.
Some races were just plain and bland and lacking of any advantages, like orcs which were like high men, but worse.
Furthermore, MOM spell choice was effectively drastically limited on Impossible. AI spell use on Impossible was invariably very similar - they would either firebolt you to death, or psionic blast you, or fry you with lightning, or drain life your units with ridiculous power. This effectively meant you were reduced to using spells like Resist Elements, Counterspell, Drain Power, Mana Leak (works wonders against enemy shamans and great with Counterspell). If you wanted to stay alive, that is.
1. The abililty to play as lots of different races and for it to be truly completely different. In MoM, playing as High Men, halflings, orcs, etc etc truly made each game a new experience. They didn't just say "every race has to have a light infantry, an archer, a heavy infantry, a catapult" and then give them different graphics. They really made each race it's own thing with unique strengths and weaknesses. It seems like just Men and Fallen is going to leave me wishing for more variety. Again I haven't seen anything so here is hoping when beta comes out I am wrong
I claim that using 'colorful' races actually reduces variety ! What can you say about most implementations of elves ? Good at bows, good at magic, perhaps stealth. That's it. Humans - plain and average. Orcs - big, strong, stupid. In most games, these races are clearly defined and lacking any depth. They mostly just borrow heavily from Tolkien and can't think of anything that makes it interesting.
Ironically, the game that showed me an amazing variety of 'races' and flavour is Dominions3. I call it ironic because 95% of 'races' are actually various flavours of humans. With just humans, Dominions 3 is orders of magnitude better at gameplay variety and flavour than so-called 'original games'. That's why I believe Elemental can do just fine with 1.5 races.
Time to back my claims up. I'll do it with quotes from Dominions 3. On Linux (there's a native version even for 64 bit - take notes, Stardock !) you can get these messages with strings dom3.
Machaka is an old sacral kingdom where the well-being of the land is thought to be dependent on the will of the king. The king is the highest priest of the kingdom, but should he fail in his duties, he is sacrificed and replaced by one of his numerous sons or brothers. The priests of the kingdom are the true rulers of the land. Religious ceremonies, judicial tasks and the gathering of intelligence are all performed by the Eyes, Ears, and Voices of the Lord. Only warfare is handed over to secular commanders. Machaka uses light infantry, archers and heavy hoplites second only to those of Arcoscephale. In the forests of Machaka, giant spiders are caught and used as mounts. One other area is left untouched by the priests: magic. Simple witch doctors living outside villages grudgingly serve the priests. In the depths of the God Forest lies a lonely mountain filled with caves. Here resides the true power of Machaka - the Black Sorcerers, Sorceresses and their Spider Warriors. Machakans prefer hot lands.
(Inspired by North Africa. Machaka has poor archers, no real cavalry, but great battle mages, very fast infantry, cultic assasins)
Ulm is a land of cold mountains and dense forests. These wild lands were settled by proud and fierce barbarians in ages past. Their ancestry has made the inhabitants of the forests stronger and more resilient to the cold climate than ordinary men. Upon becoming men, youngsters are given a single knife and left in the forest at first snowfall. Those who survive the winter are allowed to return to their family.
The barbarians of Ulm live in small settlements ruled by chieftains and warrior smiths who search for the Enigma of Steel. Steel is a sacred metal and its maker is as well. Smithing has become equivalent of making a sacrifice to the Lord and no other culture has developed such a skill in magical forging.
Ulm is a young kingdom, risen from the Ulmic tribes conquered by the fallen Empire of Ermor. From the ashes of Ermor emerged a new kingdom true to its ancient legacy, the Enigma of Steel. Where Marignon relied on religion to build a kingdom, Ulm relied on steel. The mines of Ulm are famous for their riches and the smiths of Ulm work the iron into the blacksteel armor used by the knights and infantry of Ulm. The people of Ulm are heavily built by human standards. Their infantry use full chain or plate armor made of blacksteel. The feared Black Knights of Ulm are the most heavily armored troops known to man. The leaders of Ulm have never approved of magic and only the Master Smiths are allowed to use it. The smiths are used to working in conditions that are magically unfavorable and are therefore not adversely affected by provinces that have a strong Drain dominion. The smiths craft armor and weaponry for lords and kings, but the strength of steel is preferred to magic. Even religion is of secondary importance in Ulm.
After years of civil war, the Iron Kingdom crumbled. During the Night of the Treason a great Malediction was placed upon the kingdom. The forests became dark and hostile. Wolves and creatures even worse stalked the land. Slowly the kingdom recovered, but it was not what it once was. The knightly order was all but destroyed and the Master Smiths had disappeared. The secrets of blacksteel were forgotten. An order of Black Priests emerged in Ulm. They formed an Iron Cult and forbade the use of magic. Magic outside religion was announced to be sacrilegious and the few surviving Master Smiths were put to the flames. Although magery is forbidden, there are some fortune tellers and members of the Order of the Illuminated Ones who secretly ply their trade in the arcane.
Sauromatia is a nation of nomadic warrior tribes ruled by women. Men and women fight side by side and all prominent tribes are ruled by warrior queens. This is a legacy of the Sauromatians merging with the Amazon tribes in times past. The Amazons leaders were not accepted, because they were not warriors, but they influenced the Sauromatians and women warriors gained power and prestige. Only the tribe of the Androphags has totally rejected the notion of female leadership. The Androphags are ruled by ancient Witch Kings who introduced cannibalism and man-flaying to the Sauromatians. The Androphags also use hydras from the Marshes of Pythia in warfare.
Marignon is a feudal theocracy. The Inquisition controls all aspects of the country, including warfare. The feudal lords pay tithes and tax the peasants, but all political decisions are made solely by the Church. Marignon rose out of the ashes of Ermor and has succeeded in holding the shadow of the fallen empire at bay through religious zeal and austerity. The widespread fanaticism in Marignon has done wonders for its survival thus far. The heavy infantry of Marignon is armed with large weapons such as great swords and halberds. All units carry the bright red-and-orange livery of Marignon. The Inquisitors of Marignon are trained in the House of Fiery Justice together with Witch Hunters. The Witch Hunters are mage-priests who use Astral magic.
In dark caverns under the Roots of the Earth a strange race of one-eyed humanoids once evolved. Untouched by the sun they became known to humans as the Pale Ones. When humans first met these pale giants, it was in war. With the destruction of the false god of the Pale Ones, peace was established and humans moved down into the caverns of Agartha. Here they found fabulous riches and ancient secrets. The humans replaced the Pale Ones and now all Agarthans are pale-skinned humans with large eyes. Everything left by the Ancients became subject to worship in Agartha. At first, statues of the Ancients were adored and animated by the Golem Crafters, but most of the statues were destroyed during the great war and new forms of worship have evolved. The mummified remains of the now-extinct Pale Ones are worshipped and reanimated by necromancer-priests. While the mummies of Pale Ones are sacred, the human dead are not treated with the same respect. Used for menial tasks and warfare, the dead of Agartha now walk side by side with the living.
middle T'ien Chi:
The Celestial Empire of T'ien Ch'i is ancient. Since the founding of the Empire, peace has reigned and a Bureaucracy of great efficiency has evolved. Ministers and officials chosen by skill rather than birth govern the Empire. The Emperor and his family are considered divine, but are not involved in the administration. The cavalry of T'ien Ch'i is well known and the Bureaucracy has enforced a conscription policy that has been very successful. A magic tradition called The Way is practiced by hermits and scholars in the kingdom. Prominent Masters of the Way come to the Heavenly Gate in the capital to be ordained as Celestial Masters. These mage-priests can summon heavenly beings from the Celestial Sphere to serve the Empire.
It's not even the tip of the iceberg.
It's clear from playing the game, (even demo) that for the developer it's a labour of love. Despite having almost only humans ('races' are actually called 'nations', even if not all of them are actually human) Dominions 3 has flavour and variety second to none. If Elemental has even 10% of variety Dominions has, it will be a great achievement.