Toy Display/Storage help
 

Due to my sizable Transformer collection, I actually have no room to display my MU & Joe figures. I keep them individually bagged in a zip-lock with all their accessories inside a rubber/plastic tub. They don't really weigh enough to do any damage to each other, and the little bit of air that gets trapped in the bags provides a bit of cushioning. The air does leak out eventually but it's slow enough that the figures don't get damaged as they settle into place.

I do the same with my excess TFs, but I usually transform them into the most compact mode I can get them into. I've had quite a bit of my TFs packed up for the better part of a year and a half and none of them have been damaged that I have noticed. I don't jostle the tubs around much though either, so they pretty much just stay where I put them.

^ This. I've also used the little sandwich baggies, which don't have a seal, but they still work well enough. At least no paint scratches. As far as the warping goes, I hate when that happens. The only way to help that is to not pack too much in one box/bag. It's crazy how heavy a box full of action figures can get.

I'm pretty much echoing the guys above. I keep my excess loose figures in individual ziplock bags and stack them flat on top of one another. These bags are, in turn, stored in a large plastic tote (like what you'd keep holiday decorations or winter clothes in) in a place where it wouldn't get disturbed, say a corner of a room or the closet floor.

I've also heard of guys putting moth balls in the storage bin to keep moisture down an prevent corrosion of metal bits