RTF is a global modification that replaces all towns in the game.

Humans seem a bit too strong, with two units. It would be better to have the second tier be gnomish shieldbearers; they are a much more suitable candidate than those fat guys. Especially if griffons are also available for humans.
So, it would be:
Tier 1 - shields
Tier 2 - dancers/furies?
Tier 3 - elves
Tier 4 - bears
Tier 5 - knights
Tier 6 - griffons
Tier 7 - ents