Fast shooting vs slow shooting, choose one, both are accurate and the bolt will be more reliable. Also if you want to rapid fire the bolt gun will obviously be slower.
I'm gonna stop you right there, you just said an AR-15 is a high-powered rifle. It is obvious you don't know anything about guns and I shall ignore anything you say from this point on.
I recently faced the same decision. I ended up with a Marlin XT 22MR. I would have liked one with a wood stock. But I settled for a synthetic stock after searching for 7 months. Another reason I settled on the Marlin is it had iron sights on it. I am sorry to bring the news to gun makers but I will never own a rifle that does not have iron sights. Scopes break, fog up and if you treat the gun rough they are not very accurate.