I'm team Oddsock forever. It's just a super cute dog sack. I love it. I could take or leave the rest. Particularly a bird that makes platforming irrelevant. I guess LittleBigPlanet has always been creativity and co-op first, platforming second.
Anyways, there is a lot of Sonic Boom sort of talk of distinctive silhouettes in this behind the scenes look at the creation of new playable characters, which needed to be distinct, but not so distinct that players couldn't trick them out in all sorts of patterns and clothes.
There was a Sackworm at one point, too. "Early on we had loads of different ideas. I was looking at some of the concepts the other day actually. The Sackworm didn’t last too long before he found himself on the cutting room floor!"
RIP in pieces, Sackworm.