I agree and I am surprised more people don't have an issue with it.
The devs have done a lot of really good improvements to the game but the combat changes are not among them imo. I posted some screenshots and explanations of why the changes are bad in the beta thread.
As has been said, the changes seem to remove morale stacking as a viable option for smaller nation. EU4 has
always been a game, at least in single player, where size wins. The changes don't really change the playstyle much for a single player France campaign (though the battles are still weird).
The change really hits smaller nations who can't fill a force limit, or can only afford one stack. You used to be able to stack morale and then carefully choose when to engage other AI stacks i.e. use
skill. As has been said, battles are too long now for this to matter. You'll rarely wipe the AI stack before the AI reinforces. So...quantity is now even more important for victory.
Oh, and please fix the change to stack splitting

.