Thanks Judy!! My goal is to keep it as inexpensive as possible which is why I thought trim might work best but if I can't find a way to make it look great I'll definitely look into --up tiles.

1/8" drywall sheets, taped and finished. Then painted

Burn you to death shouldn’t be a work space feature.

That is not a legal and safe habitable space. No point in decorating something that isn’t safe to occupy. Get it safe first. Drywall provides the needed fire barrier.

I should have specified this is for a storage and prep space for our business, in a detached building. It' s not an area we will live in. We've passed all inspections (I say "we" but it's been our licensed contractor who's done the work). The HVAC crew came to install a mini split but we're missing a bracket so put off the install a few days (hence the wires). I really appreciate all of the feedback.

It looks like the entry to a home so I ned a bit more info. torage ? Waht kind of business?/Ceiling tiles why . Just simple drywall in fact I think if not an actual living space just paint and trim will be fine There are lots of spaces with wood ceilings on here no drywall in sight