so, now that you've made your mind up, and decided to do "the right thing": while i hear those two lenses are great and so on, unless you are buying a 35mm body, they don't make much sense: they are the wrong focal lengths, they are probably big and heavy being designed for a bigger frame coverage. instead of getting a new canon body, i would get some lenses that are more suitable first. i would probably look closely at the two tokinas (16-50 and 50-135), maybe adding the 11-16. tbh, the 11-16 would be the only reason to stay with canon (we don't have that one, at least not yet
). now that you noticed the pentax system, you should take into account it's advantages, and decide if it's good for you (smaller size, rugged body, and lenses if you have the cash, in-body sr -- think 50/1.4 stabilized, you can't have that from canon
, and weight). furthermore you should find a k-7 or k-5 and shoot with it for a while, see if you like the ergonomics (and validate your initial thoughts about size and weight advantages, maybe you are under estimating them, or overestimating them). once that is done, see how much it costs you to get k-5 or k-7 (the k-7 is on par with the 7d for the most part, except af from what i heard, so odn't knock it), and see if, with your dream lens lineup, it's worth switching to pentax (with k-5 or k-7), staying with canon either with your current body or a new one, and suitable lenses, all things considered.
good luck
ps: yes, i know, not making it easier, but for what it's worth