I'm not going to try and convince you to stay or go. I, personally, don't buy the "stick it out because USNA is great to be FROM!" argument, but that's me.
You should ask yourself what you don't like about USNA and consider your decision through a couple of these metrics:
Peers? As you know, they're probably the best and worst part about USNA...and remember that (depending on service) a significant chunk of people you meet out in the fleet will be from USNA. You will be working with these people (or similar people) for a long time...something to consider if you don't like or get along with your peers.
Things? Hate practice parades, marching tours, or other meaningless BS? It doesn't end, the shape just changes. Actually, it kind of gets worse. I have countless examples from TBS. My Navy friends have fewer, but it's there. If the bennies from doing whatever service selection you want don't outweigh that, it's something to think about.
Future? If none of the service selections appeal to you, that should be obvious. It's one thing to grit your teeth and deal for two more years at USNA if you really want to fly/be a SWO/whatever, but it's harder to fake it for five years as a DivO. If you think you'll be twiddling your thumbs going "eff this" for five years, do yourself (and more importantly) your future Sailors the favor of not signing.
Leadership? There are good leaders out there and bad leaders. Unfortunately a lot of the latter end up in leadership positions at USNA. If your company officer doesn't do it for you, track down someone you respect from one of the communities you don't hate and pick their brain. If what they're saying about the best parts of their community and leading Sailors/Marines isn't doing it for you, maybe it's not for you.
Also, keep in mind that while you're only a 3/C now, having had terrible leaders when you were a mid never gives you the excuse to be terrible yourself. Don't get cynical because (if you decide to stay) and you try and change things in your company starting 2/C year. You'd be surprised how much influence you can have over the younger classes as a 2/C, 1/C, and particularly as a detailer. There was literally a 180 degree turnaround in my company from 2/C year to 1/C year--completely MIDN driven--thanks to my class (not so much me personally).
Academics? You didn't say your major, but there's a lot of awesome opportunites out there if you look for them. I was a humanities major who would have been cut out from UK Scholars by, like, plebe year six weeks if I had known it existed. I got my stuff together and graduated with honors, which included a partially-USNA-funded trip to Stanford to do research.
If you can't get into or don't know about special programs in your major, frankly, make them. Make connections with the profs and get one of them to back you doing independent research. At least for the history department, if the profs know you're a good dude and have a legitimate interest in the subject, they will bend over backwards to help you out and get a positive learning experience.
If you don't think that'll work out, then maybe USNA isn't for you.
In general: while a lot of the candidates or whoever on here may secretly be trashing on you, I personally, and this goes for most of my friends as well, have never held anything against anyone who has voluntarily left USNA (unless they were a dick anyway). There is nothing wrong, and actually a whole lot right, with thinking critically about your future and what the best path for you is. IMO, more people should leave USNA before 2/7. I seriously wish you the best of luck with your decision.
At the end of the day, it's going to be your ass taking the commission and standing the watch. If the idea of getting out there and leading Sailors and Marines doesn't get you fired up, you're probably in the wrong place. There's nothing wrong with that. USNA and the military isn't for everyone. Don't use it as a means to an end or any of that BS. If you don't see yourself happy, fulfilled, or doing good things as an Ensign or 2ndLt, don't pursue the commission.
But if you decide to stay do everyone a favor and don't be a cynical a-hole.