Old NAD or newer high powered Denon?

I am currently running a NAD 3020 in my main system. I love the amp. When paired with my Sequerra MET7's it sounds great. I also have a pair of Vandersteen 1C's and I am thinking that the NAD's don't have enough power to drive them. I am getting relatively poor sound quality out of the 1C's with the NAD. It closed in and not very dynamic (when compared to the MET7's). I have heard the 1B's in the past and they sounded amazing which is why I initially purchased them.

So my question is: would I gain anything in terms of sound quality of I purchase a higher powered more recent model Denon or am I just hearing the differences between the MET7 and the 1C's?