Above the kitchen cabinets

[Fredrik_1976]

Hello!
We have just built a new kitchen, with some final touches like trim and cover panels still needed.
I would need some advice on how to make it look best up against the ceiling, between the upper cabinets and the ceiling.
On one side, the gap is 8 cm, and on the other side above the tall cabinets and cabinets above the fridge/freezer, the gap is 4-5 cm.
On the side with the 8 cm gap, my initial thought was to cut a filler piece from a cover panel and finish with a ceiling trim, but on the other side, it's too tight to fit the ceiling trim, so it won't be uniform.
Tips are gratefully received!

 

[Goteborg]

Maybe a frosted glass panel with light behind it? Could be effective.

 

[Ripper500]

A gamble.
Plaster, filler and then paint? + a little grout

 

[Bloink]

Replace the ceiling molding with a string of latex sealant or similar. Alternatively, if possible, cut the filler piece so you get a good fit against the ceiling without either molding or sealant.