as for balancing I check my props to see if there way out,if there close,then I don't stress it for a smaller engine.
lets say for a 11/5 prop on a OS 46
for my warbirds then I am more diligent and make sure there as close as possible
Mfg. like Master air screw,APC are pretty close to balance.
its a good thing to check just in case there is always a few rotten apples near the tree so a trip to the balancer is always a good idea.