Regarding the servo, I just put high torque (about 5-6 kg) servo an elevator and rudder all others are std. I have fitted ball linkage everywhere and everything is moving right without "free play".
Take care on aileron travels, on first flight I have set up the max recommended in the manual and flight was a bit "bumpy" because roll rate was just too high (value measured at wing root) . I was able to land the A/C but I have damaged wings tips.
On next flights I have reduced travel by about 30/40 % and add expo, I finally get a very smooth A/C able to perform all acrobatics except torque roll.