This is going to be a mess. What would happen to PTS that ends up on an exchange? You are not guaranteed that exchanges will continue to award every snapshot.
I've been screaming about making AGS liquid, and was always pointed to PTS if I wanted liquidity. It would be a huge mistake making PTS non-liquid.
Furthermore, BTSX has a lot of room to grow, but if newcomers come in and see that there was a time to participate and they all missed it, they will lose interest.
NOTE: I think by now we all agree that PTS should remain liquid, but I find it very disturbing that locking it in stone is even being considered.