Well . . . I'm making some assumptions here, including the notion that the player is competitive in a (striking only) sport environment. I personally try to work on a few things that I consider to be standard for kickboxers. And you're right in the sense that taiji doesn't have to look like anything in particular. But I haven't seen a lot of guys (I've certainly seen some) who are able to be competitive without maintaining at least some of those characteristics.
You've got some substantial competition experience, though. Do you have any footage to counter the whole "looks like kickboxing" argument?