Rewards from general mining will drop to near zero once Ethereum goes fully to POS. Proof of stake goes by having you wallet open and how many coin are in your account. The more coins the higher chance you have of hitting a block. It actually is a better way to mine but has its flaws as well.
pros - less processing power, electric to be used etc
cons - you normally need a good amount of coins the percentage of them to hit a block yourself.
I do believe some places will be pool POS though
Pool POS does sound like a good idea, lol. I really appreciate you explaining this to me, now it makes better sense and I will start looking into ETH more from now on. Stack up as much as I can :)