I've thought about this and been tempted to try it out to see if the results were any different, but in my case it wouldn't be worth it and I know nothing of 1080P ranking above 720P so it could be a lot of trial and error for nothing, talking months of trial and error. Although when I originally started YouTube, I was doing 1080P and stopped doing it late last year, from that I noticed no difference in gaining views or rankings over 1 resolution or the other, although I did inform my subs of the changes due 1080P putting strain on what I could upload and storage space. For a gaming channel I'd only recommend 720P, consider it a luxury for viewers as a good majority of them will watch it in the default resolution which changes depending on their internet connections.