Equalization and room correction software can only change what a speaker puts into the room, they can't do anything for what the room puts out in reflections and reverberation.
Acoustical treatments are easy to do, and easy to overdo. I agree that an untreated room can never be right. Home theaters are different beasts than 2-Channel listening rooms, but to a point they can effectively share treatments. Case in point is Acoustimac's Home Theater Room Package I for $848 you get 6 2X4 2" panels covered in your choice of fabric,or upcharge for artwork plus 4 48X24 4" bass traps, likewise covered. Add to that a couple diffusers and the improvement in most listening rooms up to 200 or so sq ft is dramatic.
Because of the room layout, I couldn't use an off the shelf package In our living room, so I had them make up 16 - 2X2 2" panels in ceiling white - they are practically invisible, but made a very bright room usable, if not great (lots of glass, no drapes)
In our theater, I went with a darker grey (light control - it's a theater) ceiling panels and using a combination of white 12X48 and black 12X36 2" panels I made a 5ft wide 'keyboard' wall hanging that my gets lots of positive comments, and is very effective. I used 2X4 construction offcuts to make a 16X48 diffuser using the BBC staggering for the lengths (Warning- it weighs a ton!) for the back wall.
All in, I spent under $2K plus about $500 in hired labor to install the ceiling panels. I am very pleased with the acoustical result and the SAF is very high. Money very well spent.