+1
More Arrow Effects/Upgrades
Possibly adding a full archer "path" may entice people to pursue it more, people tend not to use the archer unless defending a castle, so if you added, say, a faster reload or possible fire arrows, that may make people want to use them more often.
Customer support service by UserEcho
I have also thought about it, adding a sort of class skill tree where, as you progress, or even use coins/gold to buy them, you get skill points, for example, at 1st, 2nd, 3rd levels you get 1 point, 4th, 5th 6th get 2, etc; And the point of this is more efficient building (takes less materials) advanced fighting (more/better weapons/ weapon effects) or even possibly getting 8-9 followers total. This obviously has some limitations though, like, what level/price can you stop buying skill points, the answer to that is stop at, say 25. have it so it costs exponential gold to buy skills (1,2,4,8,16) so that's 5 points, and make the level cap 20, and you only get perks on certain level-ups.