One way you could level the battlefield in the long run a little is to make it where each faction can only win one country. A faction that has won could continue to battle for 2nd place, etc, but with X amount of countries that will be battles, you could have X amount of winners. PUN and others could still compete for top prizes, but it would give the other top 100 or so (or how ever many countries you plan on using) a chance to get recognition and top prizes also.