I'd paint it all a cream color, maybe mirrors in the bookcases? It's a really cozy space! I love it.

If you paint it white or off-white it will make the entire space come alive.

Leaving the bottom half of the room wood, paint the top half with white cabinet paint. You will have to do some prep to the wood for the paint to look good. If possible add some can lights around the perimeter of the room to add light.

I would take a different approach and paint the built in cabinets and that wall only. I think the room is very charming. The valances look like they need to be hung higher also. From the photos the rug looks dark also, but don't get a good view of it. Something brighter for a rug and light fixture would help a lot.

The title of your thread gave me a laugh!

It's hard to suggest when all angles are not shown.
I agree, it's dark but I wouldn't paint logs (is it a log house?).
-First bring in more lighting, then lighten flooring.
-I recommend adding a stone veneer (2 walls or just end wall) of a light ledgestone....it would keep the same feel and style, but it would lighten it up plus, add value and character.
-Maybe loose the curtains also...?
Even though it's dark, I find the ceiling extremely white and doesn't fit? Maybe it's just the picture.

Whitewash to lighten and retain the character of the wood. You can also tint the wash as in pic #1.

Update! Paneling is white.

Looks beautiful!!

Oh wow!! It looks so fresh and bright, I absolutely love it!

Now it's a dream come true!

What a lot of work you've put in!

That looks great! And thanks for the update! The best part of offering the advise is seeing the outcome.

It looks so updated and fresh, beautiful!!