Hmmm, I happen to agree and that's because the most accurate listening spot is 38% away from the front wall(maybe more "correct" to call that spot the "least messed up"
). Putting the desk at the 25% spot will put you(in your chair) right around that 38% spot. Don't consider it wasted space because it really isn't. Anything that improves your listening accuracy is certainly not a waste
This is very much like my first commercial setup in Nashville in 2008 and I made that empty space into the path to my vocal booth. I also pushed the mix position just slightly off center(left to right). The space worked very well for overdubs and mixing, I just outgrew it for recording(the whole thing was less than 360 sq. ft.). The couch was on top of a risor filled with rockwool and open on the front to aid in trapping. With the bass traps and acoustic panels on any large flat surface, monitoring from the couch was nearly perfect. I did have a null at the chair of around -9db@50Hz. My solution to that was a sub(under the desk) that was tuned with a digital crossover to specifically fill in the null at the mix position. All the walls were double-walls, filled with rock wool and covered in 2 layers of 5/8" sheetrock(all staggered joints, screwed and glued). Doors were all doubled and solid core. Windows were framed so the inner and outer frames were isolated(filled the gap with thick foam weatherstripping) with 1 pane being 1/4" tempered glass and the other pane being 3/8" laminated glass(for different resonant frequencies), Even with the door bottoms not sealed, isolation(sound-proofing) was really good. Back wall of CR was a triple wall as there was another studio right next door with a guitar amp closet in that corner. I never heard it, nor did I ever hear the bathroom that was right behind the vocal booth