I am faculty at a large state university. In my experience, there are some people who have no business getting an undergraduate degree. Some people know what they want to do and that thing does not require college. I knew someone who wanted to be a Harley mechanic (which make pretty decent money) but was pushed into going to college and was wasting time and money doing something he hated that wouldn't benefit him in his ultimate vocation.

The other type of person that shouldn't be in college are those who go because they have no idea what they want to do. This type is trickier to classify as some people who don't know what they want to do, but have a general interest and know they want to do something you can get educated in, should probably be in college. This can help you figure out your ultimate goal and determine exactly what kind of training you need to do the thing you want to do. If this applies to you, though, you may want to consider a lower cost option. As someone mentioned, you don't want to pay a premium while figuring things out.

However, there are some people who have no idea what they want to do and have no interests. They are there simply because they have no better option and everyone tells them to go to college. The problem with these types is that they often don't make it. They spend 2 or 3 years racking up student debt only to drop out and find some 'survival' type job, leaving them worse off than if they had simply gotten a job in the first place.

As for the 'college experience', if you mean partying...well, you don't need college for that, you can do that anywhere. If you mean 'deep intellectual discovery', it might be easier to find people to share this with in college, but not necessarily. Education often does not correlate with intelligence.

All this being said, if you've already started, can afford it, and are being successful, you should probably finish. Finishing the degree will likely help you with whatever the next step is. The only reason to quit would be if you discovered you had a very clear goal ahead of you with a very clear path to that goal that did not involve college.

I do IT work; specifically cisco networking. This is one of the few jobs in the USA where you can easily and comfortably make enough to have to worry about doing tricksy thing on your taxes to avoid the really big hits, and do it without knowing anyone or having postgraduate education. (Entrepreneurs and skilled salespeople can make my earnings look like chump change, without even a high school diploma, but you should be able to honestly evaluate your ability to be in either of those groups). Here's my two cents:

In the USA, an Associate's Degree is pretty much mandatory if you want a good job, even in my field. In most fields which have been around long enough to be fully understood by business majors, you're going to need a real college degree - a Bachelor's of some sort, at a minimum. Most skilled workers, and most knowledge workers, fall into this category, though many of them require sizable postgrad investment. If the job you're planning on looking for relates to design and drafting, you're going to need the Bachelor's; not to get employment - that you'll get with dogged determination no matter what, but rather to ever get promoted and to avoid the list of downsizing victims when your employer shrinks.

A four-year college degree from a state university should pay off in about six to eight years. Postgrad degrees vary widely - did you get a Master's in education to teach kindergarten? It's going to be a while. Did you get a MD or JD, or PhD in STEM? Well that'll pay for itself reasonably quickly. Your four year degree is probably smack dab average, so if you're roughly 20ish then about the time you really need the money (married and with kids on the way) you'll have everything paid off and be making more than you would without the degree.

College is always worth it. If it's killing you to be there and you wish you could be doing sometihng else, volunteer to do four years in the military. Then, with your Post-9/11 GI Bill go back and finish college and appreciate a (sort of) free education and the academic atmosphere. If you've been in school for thirteen, fourteen years straight and need a break, take one. But take that break in a way that will prepare you for getting back into your education and completing it, because you'll spend a large chunk of the rest of your life wondering why so many other people have better luck than you do. Make your own luck and make sure it's good.

Very difficult question.

I went to college in the US because at college level, education is better in the US than in my country for the field I chose to study. If you have the means to do so, study in whatever place you can find the most competent teachers. Name and legacy of a college isn't too relevant, all that matters is the quality of teachers teaching there right now. Make sure you can hand pick each teacher for every course, don't take any course if you won't know who will teach it.
I have no major regrets about college, only problem was that as a foreign student I had to enroll full time. If you're a citizen of the country you're studying in, you have a choice and I clearly don't recommend studying full time if all your courses require significant amounts of homework. Leveling up various skills at the same time is very difficult. In the old days, apprentices learned one thing at a time, from one master at a time. It took a while to get good that way, but it sure worked.
It's also not advisable to have a full time job while you're studying, better to save up or only work part time. It won't be beneficial for your health otherwise. Cut back on sleep now and you'll pay dearly for it later.
Getting a degree isn't necessary in most fields so why attend college in the first place? In my opinion, having a good teacher is the most efficient way to learn certain skills. Some things you can teach yourself, other things you can learn via online courses from anywhere in the world but a select number of things can best be learned first hand from a skilled teacher. Look for the best instructors in your field and see where they are teaching. If it's a college, go there. If they teach at their private house, go there. If they teach in a public park, go there.

edit: I forgot to mention that I learned as much from my fellow students as I learned from my teachers. I used t look at college tuition as a kind of flat fee for the overall chance of being around awesomely skilled people, teachers and students alike. Sometimes, I didn't even attend my own courses but sat into the class next door if the teacher there was better than my own teacher. And years after college I found out I can learn something from random people on the street, kids included. Absolutely for free. Sure, you have to heavily filter and it's only once in a while but I'm proud to admit that I learned stuff from little children's random musings. While actual skill is rare in this world, wisdom can be found everywhere.