Anonnymitet,
I agree with most of what you said but the part about reviews.
Giving away some copies won't hurt your business if you pick the right people to promote if for you.
The one thing that made Minecraft popular was the reviews and gameplays on Youtube.
With so many big channels talking about the game, a lot of people had a chance to see the game before the commitment to purchase it.
Also, it is much a cheaper way to promote it than paid ads.