Ok the questions:
1. As far as age goes, i don't think age matters too much in terms of requiring surgery, I was 18 when I had my surgery, and much younger when i first started dislocating, 14 years old. So I was 14, about your age i'm guessing, and I ended up needing surgery, although I didn't have it looked at until I was 18, so maybe if you go get it looked at now, with strengthening, you can avoid surgery.
I also know that if you do need surgery, the younger you are to get it, the better, you will recover faster and therapy will be much easier, if you waited until you were to get surgery 30 or 35 you might need a full shoulder replacement, so make sure you get it now if you need it.
2. I don't know anything about rotator cuffs, so I can't answer this question.
3. My doctor said its possible to have recovery w/o surgery in certain cases, in my case I started dislocating at 14 years old and didn't have it looked at until 4 years and probably 50 dislocations later, which all stretch, tear, and chip all the ligaments, muscles, and bones in that joint until my shoulder was wrecked. What they did with me was essential reconstruct my shoulder. It was a lot worse than they though when they got inside, bones were chipped, cartilage was torn, and ligaments were stretched.
You might get lucky and can get away with exercising your shoulder, it really depends, they'll proably take an MRI and be able to tell you when they evaluate the images.
For me I had surgery last January so almost a year ago. Since then i've had no dislocations despite mntn biking, sea kayaking, pick up football, and day to day life. I had intense therapy which helped a ton, I'm probably at 90% mobility, and maybe 50-75% strength. My goal is to work a little on mobility and a lot on strength, not only for upper body strength, but to make the joint as strong as possible. I also plan to buy a shoulder brace for skiing and other sports, I remember it used to dislocate when I would botch a park feature and fell on that shoulder, so a brace shoulde help.
If you're looking at surgery, maybe you can postpone until may, I had mine in January thinking I could ski from march on, but when march rolled around the doctor said no. It was 8 weeks in a sling where the only time it could come off was for a shower, and then about 8-12 weeks of rehab, and no sports including skiing for 6 months. So a may surgery would put you out from may-october so you'd be back just in time for skiing, and still be able to ski this winter, maybe you could exercise it until may just to get you through, and play it safe this winter when skiing, this is of course if you need surgery.
Anyway, good luck with everything, and feel better soon.
