RE: excessive aileron play
What servos are you using? Sounds like that's where your problem lies if the slop is from the servo horn moving.
I just 'upgraded' to a fancy set of high speed, digital servos for my tail surface. Unfortunately they are also metal geared, and I am unhappy with the amount of 'slop' in the system. They are mini servos mounted right inside the stab, so my slop is probably less than yours.
For some servos you can get plastic replacement gears. I'm hoping Airtronics will come out with some for mine.
Good luck, I hope things work out well for you.