What we have now is fine. SF is game with links. Its always had links. Would more chains(ala target combos) be a good thing? Depending on how they make the game, it wouldnt hurt. SF3 had tons of TC's. They shouldnt be the main way you get your combos though. It just wouldnt be street fighter. Let MK be MK and let Tekken be Tekken.
Like I said before, I think the only thing that really needs to be changed in terms of links/combos is lessening the execution requirements for links. Meaning no 1 frame links and no plinking.
If you add an input buffer then even a 1 frame link isn't really a 1 frame link.
Bringing single hit hit-confirms back into the spotlight would be nice.