hmm, I can see two groups, one saying that the new morale is ok and it's better than before
the other group is saying this morale new feature is worst (cannot understand how it works, dropping every day without a reason, needs more boosters than before).
The weird thing is that I didn't read any comment about how the morale affects the performance of the team and the players.
For me it is as before.
Morale has a tiny effect, it's like playing instead of a 99% condition with a 85% condition.

@Lian
Superb is on an all-time high. So having your player on Superb level will unlock the possibility to have an extraordinary performance. However, it also depends on a player itself and other factors like player skills, condition, training, etc.
I bought this player this season for test and for the bench.
He had only a Good morale because he wasn't playing.
I used him in a full League game, he scored 2 (of the 4) goals and got the 2nd higher rate of the team.
He still has a Good morale.
[Official] Morale Changes - 15th of September-morale-rousar.jpg

I don't bother.
Never did