Problems, as i see it, in order of how much it hurts:
Tech is only good for a few techs, most of the tree is useless or stepping stones to good techs. Also, poorly labeled.
Magic is only good for a few spells, the other 95% of the spells are junk.
Unit design is pointless, as max armor/weapons is best option in all cases.
Champs are all clones(bland clones at that) with tiny stat differences.
Terrain is bland. Its like a perfectly flat board with certain zones(mts and oceans) declared off limits, with an even distribution of goodie huts/resources across it. This makes every map feel the same.
Population/materials/gold become ignorable, typically in that order, as just playing the game naturally you get so much you could never spend it. While metal remains rarer than ancient quests sites that can win the whole game. Crystal seems totally random, starve or be buried in it, but never a reasonable amount.
There are a lot of other little things, but those are the things that jump out as me as really hurting the game the most.