Never really had a problem with alchemy in Oblivion. I'd like to be able to make more things with it but the way it was implemented was fine.
Foot prints would be cool. Imagine tracking some giant foot prints only to run into... a giant.lol
Knocking people out would be awesome but I would hope it could last for a bit. Like, if you're really strong and you punch a guy in the face a few times he should be out for an hour or two in game at least.