Not bi-wiring, and not adding the correct tilt will make them sound less than ideal.
And, you haven't mentioned what equipment you are using.
That, I believe, might be part of the reason you aren't finding them more engaging.
I just ran an audition of Ralph Karsten's Atmasphere Class D amps at Audioconnection. All of us found the amps to be quite good, but just didn't have the upper mid/high frequency openness that the Belles amps we were comparing them to had. The Vandy's sounded good, but not involving.- Which seems to be what you are saying, I think.
Bob