suggestion: make the first class you buy cheaper (5000 or something), with an increasing cost for each next class. 10000 is waay too much. if you play this game for 1 hour every day, it still takes 2 months to get a new class ( i did the math)
conquest should have shape bonuses, like a square of 9 should give +20hpfor example. or a cross should give extra damage points, could get interesting :p