There is no shortage of modern basement ideas to borrow from. Unused basements tend to get filled with every old and unwanted item in the house from worn out furniture to childhood memorabilia. A big focus of contemporary basement designs is cost control. We needs to be comfortable and livable in such a way that it can be put to a variety of uses.

Yes, but do you know anything about painting duct work? No, yes? Method, type of paint, longevity, photos?

IMO if you really want to use the basement then do a drop ceiling painted ductwork is a stop gap solution and you won’t love the spider webs that will be a constant job. Most of the painted ductwork I have see is black so be prepared to add lots of lighting.Maybe post a picture of the basement and the ducting. We had a new furnace put in an old house it was actually moved from its old position and the installers ran all the ducting along one wall where we just boxed it in and did the rest of the ceiling drywall.This pic shows it on the left this was also a space with a very low ceiling that added to the problem

Are you sure you need to tape? The good tape for ductwork is shiny aluminum and probably not a candidate for paint. Duct mastic can seal most leaks. It would take some care to apply it to look pretty. I think it would be paintable. If ductwork is metal, it needs to be cleaned real well. If it's shiny it may need an application of "metal-prep" which is an acid. Then prime and paint.

I just had the hvac unit replaced. When it was installed several years post construction, the trunk lines ran in front of a couple of windows. And ceiling height is 7.5 feet. I am trying not to lose the light. However, the cool looking round industrial type trunk would add another $2000 in cost and STILL need to be painted. So I am weighing boxing it in again for a clean look that is in the wrong place or correctly painting the duct work...