20-30 minutes was the battle time someone here suggested - i suggested 10 min preparatin time tops.
The thing i dont like in this is that when u win in MMO u're automaticaly healed. We may have this time in the end of the game if its better. the thing is i like it when the player needs to strategicaly think beyoung a single game - for example people may try to excsost each other by having a few battles and making so much damage to the winning side that he would lose the next time. Or like "clan" members smashing a strong player of the other "clan" so they can eventualy take him down. also this requires a "retire" botton so you technicaly is defeated but you dont realy have to start over. The 10 mins can be given to you after each game and you can use them anytime you want untill the next battle, and if you dont use it - its ur problem couse it isnt acamulated.
i know its a little complex if u don't understand what im saying ill try to put it down more neetly just ask me to.