Well looks like I got a good system match with my Quad 21L. I chose them over Audio Physic, Totems, Dynaudio, Wharfedale, PSB, in their price range. "In their price range" is important here. I am sure that there are speakers costing 5X more that can trounce them. I am pretty happy with my current setup.
Heavy bass? Not enough resolution? Maybe you need to pull them out into the room. Mine are set at 40" from back wall and about 30" from side walls. The speakers are 7' apart with a slight toe-in. They image very nice. I like laid back sound. One speaker that I simply did not like was the Triangles. I could not demo it for more than 5 minutes. It was in the face presentation. I am thinking that the Rotels were not a good match with them at the demo.
I do have some room treatments now. Will update my system page soon. Before you change speakers make sure that you have "optimized" their positioning to hear their full potential. One more thing - Quads love power. My NAD integrated amp was alright. When I upgraded to the TVC+Parasound via RCA, it was better. But with the XLR in between the TVC and the amp, it is, like I upgraded the amp to a more powerful one OR like I replaced the speakers with some newer better speakers.