Over damped Room?

I have made many improvements implementing room treatment.  I have over dampenened, then gone back to reduce such.  Properly treating your room, is one of the most important things one can do.  I will continue to do so, with the advice of Jim Smith and Dennis Foley.  IMO, room treatment is a component in its own right.

trytone

The famous REG tries to listen in a "reflection free zone"

I'm not sure how "famous" REG is, but who wants to listen in a "reflection free zone?" That would be an anechoic chamber. That's no way to live, and typical loudspeakers are not designed to work in such an environment.

The reason why the famous Tube Traps have a reflective side is to prevent having too dead a room. Ditto for the Room Tune Corner Tunes and simliar products. It’s easy to get carried away and to convince yourself that more is better. Before you know it it’s too late. 😩 A reflection free zone could simply mean attenuating early reflections, which everyone agrees is a good idea.

Not everyone believes you can have too deada room. The famous REG tries to listen in a "reflection free zone"

You can definitely put in too much sound absorption and deaden the room.  It can be a fine line where just 2 panels could throw the room into a non-exciting scenario.  If you are lacking bass, try putting in some Owens 703 FRK panels with the foil side to the room.  The foil will reflect mids/high and also act as a membrane to improve bass absorption (although it really is only good down to about 80-90hz).  If you want a bandwidth limited bass panel, try GIK Monster with FlexRange limiter or a tuned membrane trap such as GIK Scopus.

Too much of anything is always a bad thing.  It's easy to get carried away with room treatments.  In my 10x14 room, I just have two panels in the front corners behind the speakers with the reflective side facing out.  A full size futon couch/bed doubles as the bass trap and listening seat.  
Generally, I prefer a live end acoustic on the speaker side and dead end closer to the listening position.