You're right about the
XBox 360's DPad - it's terrible, period. On the other hand, pretty much everything
besides the D-Pad is useful. And it's plug-and-play on PC, with most major game releases supporting it right out of the box. The analog sticks are well-done, and might work well on a platformer.
I also have a
Logitech wireless controller (F710). The D-Pad is a little better, IMO, but it's still not amazing. It's got a Dualshock-esque analog placement, which I frankly find uncomfortable and awkward. (I don't have a WiiU and have never touched their controller, but I think I'd prefer their layout with the analogs near the top.) My F710 also has very stiff triggers, and I have a tough time using the analog buttons... though I've never found a controller where the analog buttons were really
convenient, so that might not be an issue with the F710 in particular.
Honestly, if you're looking for a 2D platform controller... consider waiting for the
Steam Controller. It looks weird as heck, but the
Meat Boy dev used it and gave it a moderate approval. If you're interested in controllers for 2D platformers, hearing directly from the mouth of Meat Boy's main developer is probably the best feedback you'll get - he has a lot to say with regards to the Steam Controller versus the XBox 360 controller.