How do I layout this room

[BrainFoggerty]

We moved into our house a couple of years ago & this year can finally decorate our sitting room. It's a big room but a bit of an awkward layout with lots of windows. I'll try to attach a drawing but I'm having trouble with the layout.
Our sofa is quite big & we can't afford to replace right now. Naturally it's facing the TV! I just don't really like the layout atm as there's a lot of empty space, behind the sofa is taken up with toys so can't move it back further.
Any ideas on where to place things. DH has treated to a big TV so can't fit on any other wall. We tried soda against side wall but it felt wrong
I feel we need other furniture, a big rug......?

There's very little you can do because your walls are all taken up with doors, fire etc and your TV is where it is....

All you can really do is move the sofa forward and closer to the TV, treating it as a sort of divider, then treat the back section as more of a separate area and install a window seat with storage for the toys.

Can you move the tv? It's tricky with the fire place and the current set up.

Please don't put the TV above the fire...there's nothing tackier!

Is the TV mounted directly onto the wall or is it standing on a TV unit?

Yes to an extra large rug between sofa and TV
Some large potted houseplants
A cosy armchair by the left window
And like the pp idea of moving sofa forward

I'd pull the sofa slightly closer to the TV and have it so its aligned with the centre of the bay window.

Then move the other chair you have there to the window by the fire/TV, facing towards the sofa/fire. Big rug in front of the sofa and maybe another chair or two dotted around - possibly by the patio windows

TV is on a unit & no we definitely won't be putting it above the fire
The Windows are all actually full length so we can't build a window seat but could improve toy storage somehow - wondering about a piece of actual furniture....
It needs pictures on the walls & just some 'things' in the room I guess to make it more us. I like the idea of another armchair the other side of the fireplace. I hate the look of everything facing the TV although that's what we mostly do in this room!

I’m only throwing out ideas so feel free to disregard them all.

Depending on how high your tv is, could you have another sofa facing the first one, back to the tv? It would create a sort of conversation vibe and bring the fireplace more into focus.

They don’t have to be matchy matchy. In fact it’s better if they’re not. You can subtly add a cushion to each that picks up the colour of the other.

Add a big rug, big enough for the two couches to sit on, to define that section of the room.

Behind the current couch, I’d suggest something like a low (not visible over the couch) kallax unit with coordinating baskets/boxes and labels. Another rug to define it as a play area. Kalkax hides a multitude so you can just have one or two oversized pieces out.

How have you styled the fireplace? Is it used or purely decorative? Even adding a small log pile brings in a bit of interest and texture.

We have an almost identical room shape to you, but we don’t have a big tv in that room. We have a modest (40”) on a chest down between the fireplace and the bay window. where your tv unit is we have a large sideboard. In front of that we have a sofa with another sofa opposite the fireplace. That works well for the room. If it’s not an option for you I would consider adding another sofa in opposite the fireplace, or even an L-shaped corner unit. Seems like you have ample space, but what are the room dimensions?

Thanks for the added suggestions.
The room is pretty large, can't remember/find dimensions. The fireplace has a stove, no mantle & we're building in cupboards & shelves either side so there'll be stuff.
DH won't entertain the sofas facing each other layout, he's dubious about an armchair the other side of the fireplace but I'm insisting on that. I think that's as far as I can go with it aside from adding a big rug, some plants & updating the decor. Oh & the low Storage option behind the sofa too. Hopefully with that it'll feel more homely & better balanced.

I think those things will make a big difference.

Ime a ddog bed (or 4) fills up a room..

Do your neighbours have similar - can you have a look on Zoopla to see what they’ve done?