Why not just use a 5.1 or 7.1 wallplate that mounts to a 2 gang device box? Then add a blank plate with keystones you can configure however you like. They use them for data jacks but you can get coaxial and speaker keystones just as well at HD or lowes.
My mistake, I actually have 5 pairs on a single plate.. Thanks monoprice
So I am pretty good for that part. I have to make sure of how many of these plates that I have ordered. I also do have the keystone ones with 2 and 4 openings to cover me. For the front speakers, I need to decide if I am running 3 or 4 pairs, so I can either a 6 plate keystone or one of these 8 plate too.