With that much space around the desk, I wouldn’t worry about sound treatment to start out with. Near field take away a lot of the room issues, just like headphones. They’ll help eventually but don’t worry to start.
Also don’t neglect the height of the speakers as that will have a big impact. Typically the best practice is to get the tweeter at ear level but yours being horns I don’t know if that’s applicable. Trial and error, toe and height as the distance between the speakers is not something you can play with much on a desk.
That’s a nice room for a 2 Ch system.