What will the room be used for besides TV viewing? Any consideration to replacing the slider with a window to match the other side of the FP?

We have considered replacing the slider with a matching window. Honestly, The room won't be used for to much more then TV viewing. We don't spend that much to in there anymore.

A new rug and an ottoman coffee table would be a nice option with children.

https://www.roomvo.com/share/taz5v2

it's a bit hard to answer in the abstract (i.e., are there other sitting rooms someplace?). my starting point would be adding more seating -- some day you may want to watch TV with more than two people at a time, or even have a conversation there! put a couch on the wall that has the play mats currently (without measurements, I'm just assuming there's still clearance to walk through -- otherwise, a pair of chairs with a table between them), and get a larger rug to unify the whole seating area/conversational grouping.

if the current couch is too far from the TV for comfortable watching, you could move it up close the fireplace, leaving a walkway behind to the sliders. but again, I'm just guessing at scale here. otherwise, TV might be better lowered. I'd also switch the blue art behind the couch for the brown piece over the fireplace which will put both in better proportion to their settings.

Couch looks to far from TV and fireplace. Can you move it forward 3’ to create walkway behind it? Then you can have a seating/grouping around fireplace- maybe add one small footprint chair?

Or, move sofa where toys are now (feet on rug and 3’ behind) and 2 small chairs where sofa is (feet on rug with path to slider behind it). C-table for sofa, small ottomans/footstools gor chairs, drink table between chairs (no coffee table needed then)

If you decide to place tv on wall facing fireplace, you would then have the option of putting tv over fireplace.

This is a mount that lowers tv to eye level for comfortable viewing. There is also a motorized option.

https://www.dynamicmounting.com/product/down-and-out-manual-mount/

If you’d like, you could hang art over tv when not in use. And depending on viewing distance, if you needed to move sofa in off the wall a bit, you could put a sofa table behind it.

It will be nice when the toys are moved out, will really free up space. And I think it would also give you more of a streamlined look to have one substantial ottoman - versus a bunch of C tables + foot stools. One substantial piece = less clutter, and also makes more of a design statement.

Surprising that you don't spend much time there especially because the room is attached to the kitchen. I would get a larger rug and paint a lighter color. Get a TV cabinet that can hide the components. Paint the vents to match the wall color. Get a couple of swivel chairs.