Not that you don’t already have a lot of factors to consider I’ll add to the confusion by throwing in more. If able, you may also consider how far the speaker drivers are from the side and front walls. The timing of these reflections can have a significant impact on the sound field. So it may be that sacrificing some of the distance they are apart for better side wall placement could work better for you.
Another less often considered factor is speaker height. Most people don’t think of this in relation to tower speakers but raising them up on blocks can have a profound impact on the sound field especially in cases like mine where my seating is high and very sound absorbing. Raising my M80s so that the tweeters and midrange drivers are higher gets them better in line with my ears (the midrange drivers which having at ear level is more important than the tweeters in my experience) and above the furniture so the sound better reflects around the room creating more ambiance even with surround speakers running.
And as jakewash says keep notes otherwise you’ll quickly forget what placement changes lead to what sound changes.
