context is key.

wondering how it looks in relation to the whole room.

What room is it? a kitchen? bath?

how far from the wall is it? Just that one wall? Are you just replacing the ceiling?

Do you need to create an access to the new work? or will it be a finished ceiling in the end? are you certain you have added enough lights? looks a bit shadowy... It really depends on the finished look of the room, can you make it a feature?

The skinnier piece looks better in the photo, but if the walls are more than 8 feet or so high, the bigger piece may be more proportional.

A little extra decorative trim between the window trim and the new soffit may look good, just for the window, not the whole wall.

This is the kitchen. the room is about 17 ft wide at that spot and about 13 ft deep. the height is around 8'-5"

Thanks for info. The skinny piece would be fine with your ceiling height.

Please post an update when you are ready.

Will there be cabinets there?

Here is a picture of what I did for a customer who had a drain line running across the top of her slider over to the left of her window - it is a small soffit trimmed nicely with cabinet molding:

We matched the soffit over the larger window so it all looked like just part of the design.

I went with narrow. the rest of the kitchen needs work but I wasn't planning on doing it yet. a burst pipe initiated this project which took me away from other more pressing tasks. oh well. it allowed me to replace all the plumbing and put in pot lights. thanks for all the advice.