yeah burkhard is coooool .
Ambicephalos the Ettin Mandragora is my favourite national hero . 118 base hp , 3 armslots and 2 headslots iirc.
he is an almost as good sc as a nataraja you can give him so much stuff
mictlans 3 heros are pretty nice too cause they have strong magic and cover together with mictlans already very flexible mages almost every path
finally rylehs heros are nice too i think
and of course your mentioned tien chi ones .
most other heros though are expect that their description is stylish nothing more than a free extra national commander/mage with sometimes slightly better stats .