It's attention, not money, we should budget

30% room might be good if you have a dedicated listening room, but I think it's a bit much for a room that serves a multitude of purposes.... 

@mahgister 

You should be very proud of what you've produced with what you had to work with.  I can't think of a more relevant response to the OPs topic. 

(My reference to acoustical panels covering the glass in my wife's vehicle was an "attempt" at light humor.  I hope you took it that way?)

My own car is driven by my wife because i really put some day  acoustic stuff on the window of my car and refuse to start the engine listening music... My wife forbid me to drive since  ...I dont like it anyway...😉

it is a joke with a grain of truth here ...

In principle I agree with your premise. Execution is another element and for some the scale solidness when patients are tested and the perceived net result is not gained. The easier thing to do is throw money at the problem. 
I actually found that in my environment spending less on speakers was better. Around 20%. Moved that 10% to electronics and room 40/35 5% power and cables. 

30% room might be good if you have a dedicated listening room, but I think it's a bit much for a room that serves a multitude of purposes.... 

Maybe.  What if you keep the stereo in mind when selecting your home furnishings, and rugs, and maybe throw some panels on the ceiling?