In reply to:
I think one of the most important factor that listener forget is to do room accoustic.
You hit one big nail on the head with that one. Room treatment is paramount to get the "best" sound you can get. The ideal is a custom designed room with the ideal dimensions based on a few of those Excel programs out there as well as room treatments. Another is placement of the seating postion relative to the speakers.
Even placement of your speakers in a room can make a serious impact. I'm not talking about toe-ing in the speakers and height above floor, etc., I mean to take your entire setup and rotate it 30 to 45 degrees within the room. This has a drastic effect on reflections of sound and can minimize the amount of room treatment that is required. Instead of third, fourth, and fifth, etc reflections bouncing back and forth, they can be isolated to one part of the room before coming back to the other side. As the number of reflections increases, you of course get a reduced energy of the reflection. Thus it is important to try and contain those first few reflections.
The biggest problem with this if you do not have a dedicated media room is the WAF.