Hmm, difficult. My eldest is just about to turn 10, which is a bit scary as I have very clear memroies of that age. As others have said, I know what I was 'allowed' to do, and I have a vague idea what DS1 will be allowed to do, but it will all depend on what he's like as a teen I suppose (he's far less worldly than either me or Dh was at the same age)
Go to a party - with booze, depends on the circumstances, if I knew and trusted the parents and knew they'd be there policing it then 14/15, otherwise 16+. I went to my first when I was 14, but I don't think my parents were aware there was drink and I stayed over my friends house afterwards so they didn't even know I got drunk.
get home alone after 9 - summer 13ish, after dark 15ish. I had a 9pm curfew from about 13 iirc
drink booze - at home? No particular age so long as it's tailored, DS1 is allowed very weak shandy now and if they asked to taste something I wouldn't say no. I was drinking the top of my Dads Guinness from a very young age, and he first bought me a whiskey in a pub when I was 15. Unsupervised out of the home, I'd rather 16+ tbh.
stay out all night without checking up on them - we're not talking friends sleepovers here are we, as I don't check up on DS1 now! In fact I don't think I'd 'check up' on them ever, so long as I knew where they were and knew I could contact them in an emergency. I don't think I'd be happy with the friend of a friend, or overnight party at some random persons house until 16+ though. My parents always trusted me to be (roughly) where I said I was, and I hope to be able to be the same with mine.
have a bring a bottle party for them - 17+ with rules.