Can be abused to easy, 2 friends playing each other could take turns letting each other win. Would work better if you had a pool of players that sign up for PVP war and you are get randomly paired with a similar stat player.
Make sure you can't war some1 more than once within a 3day period to prevent alt farming, some what lol depends on how many alts you have... Maybe a x .5 plunder bonus too? And 1hr wait seems long Id prefer 30mins but that's just me
How much you get at the end of the war, is that determined by plunder though? Soooo atleast they have to fight if they want to abuse it.. I think if there was a plunder bonus that would be the biggest thin for me but I'm greedy lol
Support. The "Challenge" button would have to be in the actual battle list to make sure people don't just "war" their alts for mith. And the battle list itself would have to be updated so that it doesn't contain inactive players (e.g. those who haven't played for more than two weeks).