It would be good to have Daily Chances.
Description: Few boxes or something like that with extra exp or maybe lvl up or even warcoins. Of course it would be possible to open only one box in one day.
If there would be 10 boxes on 7 there is exp in 2 warcoins and in 1 lvl up. From this 7 exp boxes it would be 1 of 100 exp,2 of 50 exp,4 of 25 exp and these 2 of warcoins would be 10 max 20 warcoins.
If you dont understand go on this link and play game until daily chances http://www.kongregate.com/games/synapticon/tyrant.