New recruitable troops? As in, national and non-commander? Non-joke?
Abysia: Fire Drake-riders, a la LA Agartha's Cave Drake Knights.
Eriu: Glamered Slingers.
Any nation that uses Mammoths/Elephants: Some other form of early expansion. It gets old. ><
Marignon: Fire-resistant 'Guardian of the House of Justice' or maybe 'Justiciars'.
Pythium: Is there any way to make a _unit_ that gains bonuses from a communion but otherwise does not affect that communion? IOW, have a 'shieldwall' unit for Pythium that when the Communion Master gains Body Ethereal/Luck/Quickness, they also get, but it doesn't pump the Master's paths?
Machaka: A sacred troop that costs <100g.
Poison Resistance would probably be the way to go. Perhaps give them a weapon that has a secondary effect of webbing the target? Hrm, basically sacred Bane Spider troops, it seems.
Caelum: A hybrid melee/ranged unit. That way, they could use hold/attack much better, and leverage the good precision Caelum gets on most of its units.
Ermor: Cataphract of some kind? Cf. Nightmare for inspiration.
I'm sure I'll think of more.