There are some varying opinions on this. Like any endoscopy procedure, pouchoscopies are invasive, so there is always some inherent (if even small) risk when getting one done, and hence there are some physicians who feel they should be done more infrequently. However, others feel that annual scopes are indicated, and in particular, if the reason for your colectomy was dysplasia, then it may be recommended that you have a scope more often as cancer can recur in the retained rectal cuff.
In my case, I have generally been scoped every other year, except when I was having a bleeding issue, and then I was scoped 3 times in 18 months. Right now I am back on the every other year schedule, and my surgeon's office contacts me when it's time to schedule an appointment.
As to whether you see your surgeon or GI, there is really no right or wrong answer, and it basically comes down to whoever you are following up with. I've been scoped by both my GI and my surgeon - the GI when I was having problems, and the surgeon when it was routine. But that was more a matter of availability, as my GI could get me in sooner. If it's routine, some surgeons are a little "possessive" of their pouch patients and may prefer to do the scope themselves. But again, both would be qualified (obviously if they have an interest in pouches) so it's either or.
As for sedation, I've had both with and without. My surgeon prefers to sedate but that is so he can go up a little higher and he wants me to be comfortable (I was never entirely out, though). If you choose not to have sedation, the sensation is not painful, it's more a sensation of pressure, like having A LOT of gas all at once. That said, it's your own preference as well. If yu don't want to feel anything, then go for sedation. However, the good thing about skipping it, is that you can drive yourself home and go on with the rest of your day more or less uninterrupted (after you pass all the gas from the scope, of course. )