Well, in my spare time, I created this custom xml.
Download:
Ultimate Custom Stuff.zip
Extras: This enables you to have two extra sets of tracks, so you can have one for textures, one for CTs, and one for whatever if you'd like to. A SuperMenu_U is included, which contains all text for menus, races, and error messages (thanks to Mr Bean and CTGP-R). readme files have been placed throughout, telling what goes where, and what to name it, along with it's use.
Drawbacks: NTSC-U support only, unless you feel like editing an xml file. Japan and Europe may come soon, but if you want Korean, PM me, as I find it useless to put in a region that almost no one uses. Text is also only for English, but if you're reading this then you're probably fine.