Need some thoughts how to arrange the speakers

Having the left speaker fire into the kitchen is never going to be ideal. And you can't move the left speaker closer to the right because you have the TV in the way. If you get rid of the TV, that would solve the problem very nicely, but I imagine you'd like to keep it and probably in the current location.

Why not consider putting the Matrix speakers to the right, in the alcove in front of what appear to be angled windows? You might need to add a chair near the coffee table for critical listening in the sweet spot. This arrangement would have the added advantage of getting the speakers away from the wall, which I suspect is compromising their performance in the current setup.

I think you're going to have your hands full with this one. I don't suppose you could remove the yellow rectangle? If not, the only thing I can think of is to move the left speaker further to the right and no tow in. I say that because in your picture, it doesn't look like you have a clear line of sight to your left speaker.

Well right now it's only a project so I can remove or replace almost everything - all the color elements and except for the kitchen.

I recieved more and more advices to put the speaker by the right wall. But it this case I'll need some heavy curtains because it's a sunny side of the building. And no idea how to locate the sofa in this case...

looks like you don't have much of a choice here. I agree that putting the speaker in front of the angled windows (& use heavy curtains to cover the reflecting glass) is the best choice you have. Put your sofa in front of the bar table (yellow) so that you don't attenuate the right speaker (when it will be placed in front of the window).

One thing that may help is to list how your system sounds now, and what you would like to improve.