Well, the great power of this game, is that this is a different experiance. Because of that I bought one of the Founder's packs. But also, I would never do it without participating in the open alfa event. I am extremely happy of what the game is giving us and the effort you guys are putting in it. Here is a link concentrating about the games that are pay to play vs free to play.
https://www.youtube.com/watch?v=rl6d1BW8_RI
A very good example is the Titan Fall. It also introduced some new mechanics and interesting ideas, but there is a very small playerbase at the moment, mainly because players didn't want to pay to play or threw the game away because of poor matching system (small player base).
Giving this, if you want it to be pay to play game, as you mentioned in the stream yesterday, it would be best if you would provide long term access for the players, when the game goes live. For example let them create a new account free for a week or a month, let the player gather some items, experiance, ISO, give them the possibility to check how great the game is. Not only some free weekend from time to time.
Well, this is actually something that might be a problem for the community and devs in a rather after beta future. But starting to think of it now already is not a bad idea.
I hope that all will go according to your plans and we will be able to spend years having fun in AR.