The whole thing looks bad. Forget the boxes and the crown. Arched doors are always the top doors. Not the second ones down. Modern homes with vaulted ceilings do not get crown molding. None of that works.

You cannot plop a stacked cabinet on top of old, partial overlay, arched cabinets, thinking somehow, it’s going to make your cabs look current. It just doesn’t work.

For one thing, that style door would never have a stacked cabinet above. And, as @Nezumi Dezainā said, the arch will always be on top.

Take down what you done, and leave the kitchen as is, until your budget allows for a total replacement of the cabinets.

It's tough to get right. Here's how our installer did it.

@Shasta. That’s very nice, but it’s not relevant to the OP, who has arched, partial overlay cabinets. Stacked cabinets will not work in her situation.

You’re right. The OPs situation is different in that her cabs are turned 90 degrees to the slant from mine.
It is relevant, however, to the issue of how to install crown molding to die into a slanted ceiling . Maybe it will help someone else with slanted ceilings. It was certainly a challenge for us.

Your best bet is to flatten the ceiling with a soffit or use flat stock to basically build soffit with wood. If you need the crown then just do it on the front and cut a return in it. It isn't going to look perfect but it will look better than it does now.

@darbuka Did the OP note somewhere that the cabinet doors are not changing before the cabinets are finished?

As a homeowner (not designer) I think it looks fine.