It always strikes me as odd how quickly the t1-t2 and even t3 thralls become useless to a player. I don’t even bother capturing anything below t3 anymore and I am still relatively new to the game. It would be great if there were incentive to capture and use even the t1-t3 thralls such as if they leveled while being thralls, up to t3 at least. Maybe even gave them a slight advantage over a t3 for having stuck with them and all. Just a thought.
Adittionally, it would be nice if you could introduce your own NPCs to create events on the private servers, it would give the servers more longevity and make them more interesting for people to play on. The game does have a lot to do, but you eventually run out (if you even managed to find out everything you need to do for progression, since there is no true guide or anything to at least point you in the right direction).
Obviously, the game is still fun either way, but those changes would make them just a bit more entertaining.