Greetings,
As many say, long time lurker, first time poster. I reworked this post to hopefully make it shorter and clearer.

Anyway, I have been dabbling in the world of recording/mixing for a little while, and am looking to improve my current setup by focusing on acoustic treatment. I already have set it up based on some recommendations I have seen here and across the net, but have not yet tackled acoustic treatment, but I understand how vital it is! My biggest concern is the layout of the room, as it isn't just a simple rectangle.
The room is ~15x14 feet, so I know I will have some issues with it being so tiny. It has an 8 foot ceiling, is on the second floor (so no concrete...) and is carpeted. I can certainly tell where some bass frequencies are very much hyped, especially as I turn up the volume, and things become much more muddy.
The second image attached shows the "top" of the room, where my desk is located, how far it is positioned from the walls, etc. With my limited understanding, I placed everything slightly off center, and to where I am sitting, ~1/3 of the way back in the room. The 80"x11" rectangle seen in the second image holds my Mackie MR5s, laptop, and monitors. I have uploaded a couple images of this part of the room. The base of this "shelf" is 35" from the floor.
The second rectangle, 60"x28.24" is my desk. I would imagine this would be an important reflection point to pay attention to. I also think the "mirror trick" sounds like a great starting point. I will probably need to do this project in a few "segments", so I gotta figure out what will make the most immediate difference. would love some suggestions so I can know what would be best to order/make/etc for this very small room, especially with it's odd shape. Thanks you all for the help, both in this thread and for everything I have already learned!
PS - As you can see in the images I took, I have a lamp on each side. Assuming these will need to be moved for bass traps