That game did look pretty cool, but I bet it was in need of a lot more development than SRS. I just think a partially developed adventure game would be harder to complete than a partially developed racing game, and if you don't have team members thar are really into the characters and concept, it might also be less fun.
Army Men, even though 99% of the series sucked, still has a really cool concept that I think a lot of developers would be interested in working with. Not to mention that it has brand recognition...although I admit it's not very good recognition.