Thank you both for the responses. The Denon amp is set up for MM only, but I read that I can use an MC High Output cart with no issues.
A few points/questions:
1. What I like about the Sumiko carts is their broader frequency range. The RP-500M's can reproduce frequencies up to 25khz. Some of the cartridges out there are limited at 20khz. While I've never been "tested", I have very sensitive ears and believe I can pick up frequencies over 20khz. So to this point the Otello may not make me happy but the OC9 series looks like it would.
2. So to get to the bottom of it, for more warmth and fullness am I chasing the wrong animal in looking at a cartridge upgrade? Or would I be better served with separate pre amp and amp? or even speakers that may reproduce the mid range better/fuller?
Again, thank you. I am learning a lot here.