Here are the photos. Excuse the night time lighting.

The grey fad is over. Plus, this is a basement. So unless you are trying to create a theatre room and want it very dark all the time, I would not paint the basement grey. I suggest Benjamin Moore’s Ballet White. I like BM’s Natura Line.

If you would lIke dimmer lighting in the basement at times, bring in some light fixtures, lamps, etc. that are dimmable.

Oh, I wasn’t very specific about the color, I was thinking a light grey, like SW Agreeable Grey or similar. But something off-white could be the way to go also.

Properly sized window treatments will ground the room and make it look more finished. Area rugs will help define spaces - study area, tv area, etc.

I agree with above, don't make the mistake of trying to combine cool grays and warm colors. It can look nice but it is a hard look to pull off. It's easier just to work with one palette.

The other mistake we often see is that someone purchases a huge, dark sectional and when they put it in their space it looks like a giant black hole. Furniture stores are large and well lit. What looks cozy in a store often overwhelms smaller spaces.

Have some fun with the decor. Use fun bold graphic patterns or colors that you wouldn't use in other spaces of the house.

I'm also in the process of finishing the basement and after a ton of research, I am planning to test SW White Duck and BM Ballet White (mentioned above). I have BM Gray Owl upstairs which I love but I agree colder grays are starting to look a bit dated.

With basements, bigger is not always better as they can look too cavernous. I would suggest making clear separate zones grounded with rugs - a TV corner, a play area, desks for kids' projects, etc.

You have a great extra space there, good luck and keep us posted!!

It's a great space! Have you thought about finishing the ceiling? That would certainly make it feel cozier, though I know there are lots of logistical and economic reasons that might prevent this.

I'd divide the space in two and make one end into a family room/home theatre space with a big tv and comfy sofas (maybe one could be a pullout as an extra guest accommodation spot?), and keep the other end as the kids' free play area and your gym area. I'd probably get some shelving/cabinets for toy storage so the kids can use this as their space to really make a mess with toys and then have somewhere to tidy them into. In my home I need to use the basement for misc other storage (eg camping gear, tools, out of season clothes, rarely used specialty kitchen items), so if this was me I'd set up a storage area as well.

As your kids grow up, a basement is a great play area and teenager zone. A perfect place for your kids to have their friends over to watch movies, hang out, eat chips, practice for a group presentation, host a rock band rehearsal, plan a sleepover... all while staying out of your main space and minimizing mess in the "nicer" areas upstairs. We have an unfinished basement and plan to dig it down and fully refinish it by the time our kids hit their teens for exactly this reason (we've got time though, I'm currently pregnant with #1). My husband and i both lived out most of our teen social lives in our own and our friends' basements, and have fond memories.