My philosophy is to use the hardware settings gain, crossover, phase, channel level and whatever else you may have to get it close by ear.
I start my fine tuning by looking at a smoothed room response curve. If there are any major problems I will see if I can reduce them with
small speaker movements in both position and axis. You may be surprised out much difference a few inches and or degrees can effect the sound.
After that I find the range from highest to lowest SPL so I know how much cut I am going to need to get the biggest peak down even with the
deepest valley at 3db of boost. I will not go above 3db of boost unless I have to, the reason being is for every 3db of boost in SPL you need
~2x the input. By using this rule of thumb I reduce my risk of clipping which is a speaker's worst enemy.
As far as EQs go I am a fan if used properly but most people don't use them correctly. How many times have you looked at someones EQ settings
and not a single band was in the cut position yet they had some cranked way up.
Equalizers in the digital domain are worlds apart from analog technology but it can still cause issue if a person isn't mindful of the potential for clipping.
MC does a lot to help though due to it high bit floating point structure, I don't completely understand it all but I trust the guys serving the cool-aid.
When it comes to the Parametric EQ I only have one problem with it and that is the name because it is so much more than just a PEQ, it is pretty much
a full DSP on it's own. (pic)
I realize you are limited on options for component placement so I spent a bit of time looking at the various items/angles in you pics.
Here are my suggestions take them for what they are worth.
I would swap the table with the monitor and reel 2 reel on it with the 1 with the candle sticks and place the sub underneath it. This would allow you to widen
the sound stage a bit. I would also move the rack inside of the left speaker or place it where the sub is now, not sure because I don't know which cushion on
the couch is the Throne and there isn't a view from directly behind the Throne to get a better representation of the sound stage center.
Just for a bit of background on why, here is what I have read that you want.
You and the speakers are all equidistant to each other (equilateral triangle)
The speakers are equidistant to the walls respectively but not equidistant to the side and back walls comparatively (both are say 20" from back and 30" from side).
I am OCD so when I started after my recent move I had my speaker laid out to within fractions of an inch, they went in before the furniture.
Well that is my .02 for the day.