I tried posting this once but I cant' see it anywhere so I'll try again.
I'm concerned that this version will restrict the current players methods of sharing and trading Koi. Previously, while we were always restricted to 20 friends, we were also able to have a sort of pool of reserve friends that we could switch out at any time. This made sharing with many many people very easy, and made asking for and offering koi on the fan pages feasible, as temporarily adding a friend was easy, as well as switching back to a core group without trying to remember names. Now, asking for and offering koi is going to be harder, as people may be unwilling to delete accepted friends.
With a small friend base, and no 'reserve pool', I'd suggest either a wish list in game, or the ability to send messages in game.
Otherwise, the new system has been performing well for me. I really like the new 'active' feature.