I would expect that Chelsea will handle it differently next time. January is only four months away and Everton will still be in a very strong position regarding the length of the contract held by John Stones.
No manager will want to disrupt his team half way through the season and Chelsea will not be stupid enough to try to bully Everton again.
I do agree that next summer John Stones could well leave, but to where, don't rule out Utd , City, Barca, Bayern, Madrid.
Stones is high profile now and will be watched closely, if he has a good season he will be very much in demand.
By then hopefully Mori will have settled and both Galloway and Browning will be more experienced, Pennington as well.