Soak them in vinegar overnight and then dip them in a warm soapy bath for a few minutes, then wrap them in dead fish and finally throw them over your left shoulder and the ones that stay in one piece are fine and the broken ones, well you don't need those anymore because they're broken right? Thus you've reduced your weight to box ratio by 60% and you don't need a large box for them after all, and because you've stripped all the paint off with vinegar you'll have no problem with squishing them all up into a small box without packing materials so you've cut your overheads down by 80%.
Sorted.
Or you could do what I do and buy a large plastic lidded tub, buy some garden fleece (used for wrapping delicate plants in winter, cut the fleece into a long strip the width of the tub and lay a strip down in the bottom of the tub so it hangs over the side. start at one end of the fleece and lay your figures down on it with their accesories beside them, then when you cover the bottom of the tub you fold a layer of fleece over the top so it ends up hanging over the side again and you keep doing this until you have all your figures layed out in layers with a layer of fleece between each 'slice' of figures. It works best if you alternate the way the figures lie, so one layer is north to south and the next is east to west etc. Spreads the weight a little more evenly.
This is how I packed up my entire star wars collection for moving. Wrapping figures individually is a pain so be economical and do it in layers. Fleece with protect your figures from rubbing against each other and chipping paint, plastic bags might keep dust off them but they can still get knocked and scratched by other figures through thin plastic. Obviously you can get different thicknesses of fleece so go for something of a medium thickness like a quarter inch to a half inch. And if you can't find garden fleece then fabric stores will have the stuff they use in quilting in various thickness. For the sake of protecting your figures it's worth spending a little I think.
The stuff I bought was five foot wide and ten feet long and I got two long strips out of it that did me three large plastic tubs worth of figures getting roughly nine layers of star wars figures to a tub.