I first would go with white FP as Cloud White BM

and light walls such a Classis Gray BM

or Gray Mist BM

Then you will see if you want to paint wood work.

here is youtube video link that I love how Sharah did renovation similar to your living room in Tulsa.

ohh forgot. I would paint the same color as walls inside built-ins instead wall paper.

I like Celery's suggestions, but I'd go for a warm white in a dark room, not gray. Wouldn't paint the woodwork.

Oh, and keep the dog...

If you paint everything the same color you will lose a lot of the detail that really makes your room beautiful. Would you consider having the trim, base and cabinetry stripped and leaving the natural wood tone with a coat or two of rub on polyurethane?

Yes! This house has so much character still left( laundry shoot, stained glass, 2-fireplace etc) and the left back of this room entry is actually pocket-door(black color)!

Most trims of this home is painted in white, except for the entry hall & this dark room(black trim).

We’re open to strip to natural wood, but we need professional to do it(we’re not handy).
What kind of professionals should we ask for these type of job? Regular Handyman service?

I also thought about adding wallpaper bottom half on the wall (something vintage look lighter tone pattern) !

This dark on dark scheme seems oppressive- might have worked as a den with leather furniture but empty it is just heavy. Cheapest is to paint the trim white to match the rest of the house. Stripped would be better- unlikely a handyman will have the skills. Some paint companies do, or a furniture restorer. It isn't hard just fussy, heat guns, sanding... Sometimes if not prepped well the old paint isn't well bonded to the original varnish.

Gorgeous home; congratulations!
I hope you’ll decide to go with restoring the natural wood. I’m not a pro, so I can’t advise you on that, but if this were my home that’s absolutely what I’d do. It will be beautiful!

I’d reach out to a local wood worker.
Someone who makes built ins in your area
I’m totally obsessed with wallpaper so I’m going all in with some ideas I have for you :)
The first is my absolute favorite!!!
https://www.houzz.com/products/york-wallcoverings-at4229-blue-book-champagne-toile-wallpaper-blue-white-prvw-vr~156177596

Since this is a a home built in 1910, I'm going to guess it is Craftsman style. Natural colored woodwork would be most authentic. If everywhere else in the rest of the house it is already painted white, I guess you could paint it, but that makes me cringe. In the '80's - '90's when my friends and I were all buying our first homes, the people who got old homes spent hours removing paint from woodwork. Now apparently the Millennials have come around and painted it all again. :-) Everything goes in cycles.

My suggestions would also vary based on how you're going to use the room. Would taking the room from dark and depressing to warm and cozy work? That wouldn't necessarily be light and airy, but would be suitable for a home office or TV room if that's what you're going to use the room for (unless the person using it for a home office likes light and airy).

Your floors are a warm color, therefore be careful to use warm colors on the walls. The gray is definitely oppressive. Look at BM Historical colors. In character with Craftsman style would be ochre, a rusty orange, or olive. If you're not as interested in replicating a historical color scheme, just use a warm white. However, don't paint this room without taking into consideration how the rest of the house is painted so the whole is coordinated. If you do decide to paint the woodwork, paint the walls a slightly darker color for contrast so the trim has a little pop.

IMO, the wallpaper suggested above is not in keeping with the style of this house, so unless it is going to go with the rest of your house, I would explore other options. There are definitely Craftsman wallpapers out there, but they're usually not done in light colors.

Suggest you get a couple of bids on removing the paint and restoring the original wood finish. The cost might help you decide whether to restore or repaint. Beautiful house!

Thank you everyone for advices!

adding 2 pics for reference:
one is before pained current color, looks like original trims were not as dark as black, but pretty dark stained(?).

Second pic is current color scheme from another angle where you can compare wt living room + white trim merging into this room.

Planning to use this room library/study, but not making it too formal( adding window seat cushion, dog bed obviously!lol)

I LOVE original wood restoring, but also worried about the balance wt the rest of house- maybe restore wood surface of book casing/drawers/ pocket door and keep trims as is or paint white like the rest of rooms could be the good compromise 🤔…

My first reaction was how the trim is actually taking away character in the room, by not allowing other features to be appreciated. Painting the trim the same color as walls will make the room feel calmer and larger. I’d also recommend the fireplace be the same color for a less broken up look and add large art to cover niche as well as take away from the expanse of brick.