You won't believe this but I had a Byron Pitts, a very long time ago, back before there were all these fancy servos. It had a Q42 in it and weighed 17 lbs. I had 4 - S148 servos in it, 1 for all 4 ailerons, 1 for the elv. 1 for the rudder and 1 for the throttle. For those of you who don't know these are standard bushing type servos with about 45 oz. in. of torque. I flew this thing for over a 100 flights and sold it to a guy who put another 100 on before it hit a post and scattered foam pellets all over the field.

I know you won't do this, but it can be done, so IMHO standard servos will work for everything except maybe the rudder, I wouldn't do that again, but it proves a lot of what we do today is overkill.