im kinda confused why you are using the subdivision preview at all when the target for the model is tf2. tf2 barley uses normals at all so there is no need to do a high poly.
The same reason Paperman did it, to achieve an absolute traditionally hand drawn cartoon look. I don't see motion capture/ morph target animation doing that and that includes Ni No Kuni.
Will the technical guidelines for character art be posted as the contest starts?(texture sizes, target poly count range, and etc) or we aren't limited and these characteristics are just a nice plus to the finished model?
When stitching 1 to 2, sometimes you need to stitch 2 to 1. <---(Ancient proverb? LoL) If that doesn't work you can target weld the points, but that's a lot more clicking.
It can be a good practice to open the mouth and close the eyes slightly. That way you avoid deep creases around the mouth and "dirty eyelids". Morph targets/blend shapes can help with that.
I think Autodesk are the main targets of piracy. Modo's price isn't that bad. With what Autodesk charges though, I do kind of have a hard time feeling bad for them.
I don't think you can use the twist modifier for the game engine. Unless you are exporting a Morph Target per frame. This is just a bunch of dummies linked top to bottom.
I don't think there is a way out of the box in Maya to convert wrap to skin. But you could just as easily apply skin and copy the weights from the base object, that the wrap was targeting.
You should be able to target weld the vertices, unfortunately i don't know how to do it in Maya Edit: Apparently maya uses Merge, which is found in the edit mesh tab.
Maybe handplane should come with a test assest with different normal maps included so people can test what tangent works best with a target engine if it's not one of the featured ones.