On that account I think there should be a bit of more "exoticness" anyway, and also that "upgrade-feeling" you get currently from normal units.
Example: Ljosalfar (spelling?):
warrior > archer > longbows > flurrys
I've played a bit of DnD myself and would rank the "Giant Races" the following way (from least to most powerful): Ogres > Trolls > lesser Giants > "higher" Giants. By "higher" Giants I'm thinking Storm Giants and such.
However I think there should be some kind of "Giant" for various Civs:
Svartalfar: Trolls, Hill Giants
Ljosalfar: Forest Giants (these exist for DnD 3.5e and resemble giant elves)
Clan of Embers: Fire Giants (they follow a "fire theme" right?), Ogres can be the earliest "Giants" available.
Illian: Frost Giants (Wilboman could be some sort of Chieftain)
Doviello: Trolls, Hill Giants
The more "traditional" "human only" civs would get high-level cavalary, siege engines and such instead of giants. Also, just as the various Cavalary and siege engines get upgraded versions during the game, the Giants should get upgraded versions like "Hill Giant in loin cloth with a Club" advancing to "Hill Giant in Leather Armor with a Sword"
I'm a big fan of the Pact of Nilhorn simply because I like the Giants, so my vote is definately for more Giants

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