Welcome to the forum Muffin. As Greece Lover said, some people push certain treatment modalities. I find that most people are advocates for whatever method they've chosen be it open surgery, radio surgery or observation. Doctors will recommend, for your particular case, whatever treatment they do, be it translabyrinthine surgery for ENT, retrosigmoid for neurosurgeon, radio surgery, using whatever machine they've got, for radiosurgeons. With regards to observation, look at pubmed using "conservative vestibular schwannoma" to get that viewpoint covered.
Talk and read as much as possible, but ultimately it's your decision.
How long have you had symptoms, what are your symptoms and how large is your tumor?
You mentioned something interesting, "For being a rare tumor, it sure seems like there are lots of people with it!" Would you believe:
* ~1 in 100 people with die with an acoustic neuroma, most not even realizing they have one [from autopsy studies]
* ~1 in 1000 people will be diagnosed with an acoustic neuroma in their lifetime
* 1 ~ 2 people in 100,000 are diagnosed each year