I say go for it too. He sounds like he's been handled enough by experienced horse people to be easily trainable. The picking up the feet thing sounds really good. Alot of people never teach their young horses this and never have their feet trimmed until they are a big strapping 2yr old and then they wonder why the farrier is put out with them.
Like the others said, bottle babies are more pushy. I think it's because they think you are just another strange looking horse and can be rough-housed with accordingly. Just keep in mind that every time you interact with a horse of any age that SOMEBODY'S getting trained, one way or another, for better or worse and you've just got to make sure that it's YOU doing the training and not the other way around.
Horses assert their dominance over each other by testing who makes who move their feet. Don't let him barge into your space and don't let him touch you with any part of his body unless you ASK him to. Especially don't let him get away with putting his mouth on you. For some horses, it's like a game for them to see if they can do something they know their not supposed to and get by with it.
Sorry this post was so long.
Frog, you are so right and just described Tuffy to a tee. He's 6 years old and still likes to try and see what he can get away with, stuff he knows is a no no. One of my rules for my horses is that if they have a halter and lead on, no eating. They tend to want to drag me or my kids around when they are allowed to eat when haltered. Tuffy still tries to put his head down, even though he KNOWS he's gonna get a jerk if he even acts like his head is going down. My other horses don't bother trying.