Move your chair closer will be the only solution. Also your speakers are very tall and they do need wider and larger room. According to your pictures, I see yourlistening position should be either standing or you can place bar stool instead of chair. In my experience forming the equalateral triangle is where you should begin and probably end.
Can I move speakers closer to sidewall if...
I treat the 1st reflection points? My room is not very wide (9") so right now I have my speakers positioned about 1.5" from the sidewalls measured from the tweeter. If I treat the 1st reflection points can I then move the speakers closer to the walls? In such a narrow room I am always looking to widening my soundstage.