The WWW is soft, but I wouldn't say it's the softest. I'd give that to the Signal Park Rocker. That thing'll flex just holding it. The WWW will do everything you need in the park except for pipe and large kickers. You could even take it out of the park, but just don't bomb down hills with it.
The Indy's aren't bad bindings. I'd just put them in the beginner category. If your budget permits, step up to the K2 Formulas or look at Rome 390s, Ride Contrabands and their Mvmnt series.