There are the pictures of my mixing room. In making, of course. Sorry, for the mess.
Front, listening position. The boxes on the table are placed where the speakers will be.

Back, right of the listening pos.

Back, left of the listening pos.

The room is 3x4m, 2,4m high.
Here's a quick drawing of the main objects.

Now, I have the possibility to remove some closets. The dark ones would be the first to go, since they're also poorly built/old.
The big wardrobe will have to stay.
The room has some noticeable ringing/echos. (I tried clapping) Especially near/right behind the listening position. There's significantly less ringing in the back of the room. Could it be because of the big wardrobe?
I'll be soon placing some rockwool panels. And a carpet on the floor.
Should I remove (some) closets or not?
Should I rather stuff them with something?
Should I use some cardboard boxes somehow, since I have many of them?
Thanks!