No living plant will thrive in that location. It is more of a cave than an awkward space. I'd go with some sort of built-in or if you absolutely must, an artificial plant. But that would never be my first choice.

Do you mean that you want to take the TV setup out of the alcove, and install a grow light setup instead? That's absolutely possible, a lot of people have success with indoor growing. Some people like to use a wire shelving unit, sometimes a bakers rack or other something for plants to sit on. You would have to be willing to have the grow lights on a lot of the time.

Making sure plants aren't toxic to cats is important. Also important, how do your cats react to plants? Some cats don't care at all, others will mess with any plant or race up any tree they can get their paws/teeth on. Or might want to mess with "ribbon" plants, but ignore others... and other behaviors too. If your cat(s) want to mess with everything, skip anything they can get to. As in floor pots or cabinet jumpable access. Perhaps consider a hanging basket of something instead.

Yes, everything in that photo will be gone and the alcove will just be, yes, a cave.

A bakers rack with grow lights is something I was wondering about if putting a tree or plant is not feasible under lights. I can run lights about 10 hrs per day. Would herbs do well in that set-up? I am planing to grow a bunch in the kitchen, but if I can save the counter space that would be good too.

As for the cats, hard to say - with fostering it wiill sometimes be kittens zooming around, other times maybe some settled old ladies :) Hoping with cat grass and toys they will be uninterested.

Grow lights work okay for starting seeds or assisting low light need plants but they do not replace actual all day sunlight, which is what almost all herbs want.

Find another use for that dark, cave-like alcove. It is not suited for live plants. I like the idea of a bar :-))

Sure, you can grow a bunch of herbs under grow lights at 10 hours a day. If you want, you can grow micro tomatoes and tiny peppers, bush beans, a bunch of leafy things. You have to be a more intense gardener to dedicate yourself like that though. Indoor gardening can have it's own issues.

I used to run an indoor garden in a interior room in the winter. It wasn't big, around 100 sq ft. It was hydroponic and container. Grew herbs, tomatoes, beans, leafy things. It was a challenge to keep everything fed and watered right.. and avoiding things like mildews and critters. It was a lot of work. Great learning experience. Now a days I tend to keep it to some square inch gardening with greens and herbs, sometimes radishes and green garlic- and I don't use the interior room anymore.

If you want to do grow lights, get LED lights. The old tubes are old school. You need to make sure you have good air flow in the room, like outdoor breezy. Having your ceiling fan helps with that. Depending on how much jungle you grow, you might need more fan action.

Since you say you foster... you might want to consider potentially installing doors on the alcove to keep kitties out. It should not be solid, I've used window screen material and hardware cloth in the past to deter kitties. I had a cat that was willing to climb chicken wire, so beware there.

While, with a lot of work, plants can be grown indoors under lights, I think the OP is looking for some pretty room decor rather than an intensive gardening project. Personally, I find grow lights too ugly for a living area and I wouldn't try to grow a house plant in the alcove. I'd put it on a stand in the window and use the alcove another way.

You could put a bar across near the top & hang some Pothos there. It won't need much light augmentation, if at all. I'm picturing 3 pots, with the middle one hanging a bit lower. Most of the vines would dangle, and I'd wrap a few around the bar at the top. Just don't let them get a grip on the wall. It leaves marks on the wall when the roots are pulled off.

I would put the 2 existing plants on a table as close as possible to those beautiful windows.

No idea about the cat toxicity thing.

"No idea about the cat toxicity thing."

Most of my plants are toxic/poisonous, have had cats for over 35 years, they all have passed from OLD AGE. Had a cat with cerebral palsy, supposed to survive maybe a week, she lived for 20 years despite all the poisonous plants. Cats ain't stupid.