I saw the Shapeshifter: The Epitome thread, and while the setup in the first post does seem strictly superior to what I'm going for, it's not applicable in this case. DM's got some fairly strict ideas about usable races, as well as shapeshifting via spells, else I'd start with a changeling or lycanthrope or do it with spellcasting, and not worry about wild shape so much.
As it is, I'm hoping for something that can be accomplished with a tiefling using LA buyoff (or better yet a half-fiend using the progression class and buying it off multiple times, but I'm not holding my breath on that one). Hengeyokai isn't available regardless. :/
I might be able to talk him into allowing all shapeshifting-related classes to stack their levels to determine wild shape HD limits, but I'm looking for something a bit more solid if not. The wild shape amulet should work, and he probably would allow increasing the market price to increase the level improvement it grants.