Listening room setup - please advise

Here's my room where I listen to the music and work.

Wanna rearrange it to get optimal SQ.

I post the picture of my room plus some additional info.

When I sit behind my desk my ears are at 110 cm.

A, B = Speakers Dali Concept 2 - they hung at the hight of 155 cm, above my head before me.

C, D = Speakers Dali Zensor 1 - they hung at the hight of 160 cm. They hung behind my back.

Sub = Subwoofer: Rel T5

Please advise placing the speakers, their hight, position.

Should I place Concepts in the back, and Zensors in the front, at different levels? What about the sub?

I appreciate all the recommendations. Thanks.

Ask me anything about the room and current setup.