You probably won't be able to hear the difference as long as you get it back real close to the location. Even if it was off by a 1/16th an inch you may not be able to tell by ear.
I wouldn't touch anything but gain.
However I sincerely doubt the gain is the problem. The only thing that would make sense for that is if the room somehow was gobbling up the bass frequencies.
I am not certain that it is the room. The Exotica 3s have front firing bass drivers. When I stand in front of them, I don't hear much energy coming from the bass. There is some energy, but it is not much, and one would not be so impressed. My preamp bass setting is at zero. (Even with no bass output from the subs, the detail is still amazing with the Exotica 3s.)
If I swap it for the Soundscape 8 in the same equipment - there is no comparison. I would have to turn the bass control down from -6dB to -8dB (3 to 4 settings down from zero). Still - there is no comparison. I can have the Soundscape 8 placed anywhere in the room - and still have no escape from the deep, lush, rhythmic bass that it offers. The Exoticas are not even trying to compete - so it may be a gain issue, or a power issue
So I don't believe it is the room acoustics. I should know more tonight when I get home and will post my results.