I wouldn't use a warming filter, you can adjust the warmth of an image by tinkering with the White balance. As it has been said in the post above UV filters are redundant. The glass they use in lenses these days are terrible transmitters of UV light so the point of using a UV filter in the first place is negated by that fact alone. Secondly,I would recommend getting the best polariser you can get. I have seen a bad polariser completely trash the image quality of a lens. The pro1 digital filters are a good place to start. The Pro1 filters still suffer from flare but compared to the comparably priced filters from other manufacturers they are slightly ahead of the competition.

If you are buying a filter to protect your lens I would say forget it, borosilicate glass they use in lenses these days is pretty damn hard. If you really want to protect your lens, I suggest you get into the habit of using the lens hood. Of course with a lens purchase canon typically doesn't provide the lens hoods with non-L lenses - A policy that is damn annoying.