Well, different people will have different opinion about this game.
But i'll add another comments about this game, Differrentation wise, i think that has to do with we being able to play all races at once in 1 playthrough, if that feature is removed, there is a good differrentation.
Spell wise, only the damage spells which function the same, to damage yet with different animation, other spells if you really pay attention to each of it, you'll notice that one do very different thing with the others, ok maybe the damage buff is just the same but with different damage type, but the game gives several type of resistance, this made those dmg buff spells very different, like we will never use a death damage buff againts undead, etc. Still, there are no dmg spells that has identical role, just like elemental, you got early damage spells both single target or AoE, then later you got the better version, after getting the better version, you'll mostly use that, every game like this have that, even MoM have those. I think that same value or animation didn't matter that much, what matters is the spells role in real competitive gameplay. Right now, the ai is dumb, they don't use their spells wisely, but the developer promise multiplayer dlc, and imo the fast pace of the game means that it's good for multiplayer.
And like most of people said above, what this games severely lack is empire building depth, unlike civ and elemental, but then again i think this was never meant to be a game such as that, it is more of elven legacy with MoM flavor (magic) created with the style of majesty game. I admit i was disappointed at first after looking about the lack of depth, but the more i explore the game, i think this game has potential, with couple of patch, it will turn out good. Another factor is the AI, if only the AI is better in using spells and purchasing equipments, the game will be hard, since this game is about racing to late game content, the AI often gets there, but they never use it, which made some aspects of the game look pretty overpowered, like god units or late game items (adamantium armor and the like), if the AI also use those, they'll be even with players, or i dare say that the AI will be better than most players, since they have cheat (like gold dragon spell summon, more income of gold,mana,food).
Though if compared to FE, imo FE still better in most thing, but the balance is so screwed, i care so much for balance, more than depth, fortunately it is still in beta, and i usually keep my distance from any thing beta. I hope that FE will be balanced. But unit variation in FE feels bland, just like WoM, most of the units are just those soldiers that we designed, they just feel bland, if only FE will give more monster army to recruit, i might be tempted to try the beta myself.