Well what version of E5-2650 would you get? Each xeon can cost you anywhere from 300$ at the worst version all the way up to 1,000 each for version 3. For gaming the i7-6700k is actually the best of the 3 options hands down. Basically, if your having trouble with editing than the Xeons are your best bet due to the huge amount of cores. However if you don't need better editing performance so badly that you are willing to spend $600-2000 to improve it with the Xeons, than you can get the i7-5820k to give you a bit better editing than the i7-6700k. Even though though the 5820k wont do quite as well in gaming as the 6700k, it will do better in gaming than the Xeons.
EDIT - As another alternative, you could consider an intel i7 5960x which would give better editing performance than the other i7s without loosing much as far as gaming goes. Also even though it is around 1000$ I assume it is in your price range seeing as how you were considering dual xeons.