soundproof headphones plugged into your alarm
i did this my entire freshman year, worst case they fall out and you have the alarm play over both headphones and speaker, 0% miss rate
and honestly? as annoying as your situation sounds, you're not alone and i almost feel like i had worse. Yeah your roommate brings friends home (is that really that much of an issue? at least you haven't been loveiled yet..? it's his room too) and plays music... it doesn't sound like he's personally keeping you up all night (for reference, my roommate kept the overhead light on until 3 or 4 am every night and played BDO, screaming in chinese all night)... so... idk what to tell you dude. best you can do is confront him about your concerns, because from my understanding you haven't talked to him about it at all and have just posted about it here (maybe i'm wrong here, if i am then shrug. sometimes you gotta deal with these things).
On other fronts, I feel like your best move is to drop some cash on a cheap notebook laptop and just get work done at libraries. i don't know what your major is but generally they can handle most school assignments (my friend has gotten through 3 years of a cs major on a $130 laptop that can't even run hearthstone), and yes, you won't have access to your desktop at all times but worst case you can set up remote desktop or something.
and finally in regards to A/C... remember that you're in an entire building of people who are likely suffering just as much as you. yes, there may be other buildings with AC, but unfortunately that's the way life is sometimes, and people can't accommodate your every whim because believe it or not there are a bunch of other people who would gladly switch buildings as well. It just doesn't make sense to me to complain that you're not being switched when i'm sure there are at least 100 other people who would want to.
and ninja: i realize this is coming off as passive aggressive as forget but we had someone on my floor in freshman year that complained about a lot of things like this so... it's a bit of a pet peeve
