I would echo what others have said. Move the sub to the corner, this is likely to add several decibels of boundary reinforcement to the output. This may or may not be welcome, depending on the specifics of your room and audio system.
For your speakers, arrange them symmetrically in the recess of the room, move them further away from the side walls and closer to the center and pull them out a bit from the back wall as well. This is likely to improve the sound stage. While you are at it, play with the toe in a little to see if that makes any improvement for you. I also couldn't tell from the image, but you've stated that the table is bowed. Grab a level and make sure that your turn table is sitting level (middle of the bow). You might also be able to slip a block of wood under the center of the table to remove the bow a little. Paint if brown so it blends in a little.
Each of these changes is likely to have some impact on what you hear - it will be up to you to judge whether or not you like these changes...
« Last Edit: March 27, 2020, 02:44:10 PM by EricS »
Eric
Haven't electrocuted myself yet...
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