First of all, the point 500 limit is way, way, way too high. Typical match looks like that: around the 100th point one team starts getting distinct advantage, people on the other team start mass leaving, and for the final 300 points it's a 4 vs 12. Spend three matches like that, one-sided fight at the beginning and then a 10 minute wait filled with chatting about the philosophy of Moa Birds*. There was only one match, which we lost 485-500, that was interesting up to the very end.
Making the points speed up or lowering the limit would probably stop some leavers, for not everyone is a connoisseur of fine serious discussions. Please, ANet, if it would be possible to change by the end of the weekend

Secondly, I understand that the 4,4 and 4 instead of full 12 parties are there to make finding groups easily. This backfires, because it often feels like a 12vs12 random arena. Perhaps make an option to create 12-people teams for those more patient players? Dunno, it's hard to strike a balance here

Thirdly, please make a level requirement. There's always, ALWAYS a hapless lvl 4 running around, God knows why

These are first impressions after just a few matches. Off to play some more now, add you own thoughts.
*Seriously. We concluded that they are neo-heglan. And communist, but just in order to wear Che Guevara shirts, because they look good in red ._.