The first thing to do is get a measurement microphone and a problem that gives you frequency response and group delays. After that get dirt cheap 4” acoustic tiles and place them to eliminate group delays (first reflections) and smooth frequency response trying to make both channels as close to each other as possible. Then you can replace the tiles with better looking treatments if you like. Every time the wife moves things around you have to remeasure and tweak. There are ways to do this blind but they will never be as good as using a microphone.
Room treatments for a lively sounding room
I recently remodelled my 10 x 15 listening room as well as the adjacent room it is open to. New paint and hardwood floors now instead of carpet. The room sounded to "shouty in the midrange". I bought a large area rug for the room but the room was still too "lively" sounding. Tried putting a blanket on the side wall not adjacent to the open room. Sounded much better, but unattractive. So just I installed a multi panel room treatment kit from Primacoustic last night. I was just curious what other members of this forum have used and what room treatment experiences have worked best for them.