That's how I do it, actually. It's pretty easy, really, to just look at the assortment on top of the box and pick the most obvious thing you're feeling around for... In the case of the dwarf, it's his axe blades, or his helmet as pretty unique. Also his short legs.
Every figure has a couple things you can sort of pick up on... Snowboarders or surfers with the big board, fisherman's fishing pole, the "tail/spine" of the Godzilla guy is really easy to pick up on. The monkey in the last series had a banana, and the monkey wrangler in this one has one too, and it's pretty easy to tell what it is through the packaging. I find elves from the last series by the bow and arrow.
I picked out dwarves and elves for the kids and myself, the Gladiator by his helmet (I have two opened if anyone wants the Gladiator)... It's become sort of fun to pick them out for me, but it can be time-consuming so I try to do it all in one swoop when a new set is found, so i can just get them and be done looking, haha.