@voodooman13 Upgrading speakers will likely be the most immediate path to getting significantly better sound. The F36 is a nice speaker, but you have other options. You owe it to yourself to visit Destination Hi Fi in Los Angeles and listen to a set of Legacy Audio Expression. The Expression offers a ribbon tweeter and 38Hz bass extension, and weighs in at 70 pounds, while the F36 weighs 50 pounds. The Expression has 8" woofers vs 6.5" woofers on the F36. The Expression will give you the low frequency dynamics you mention, in spades.
http://destinationhifi.com/For a real tweet, while you're there, have them connect the Expression to a Raven Audio Osprey tube integrated amp!
BTW, I'm pretty pleased for now with the audio quality I'm getting via my Denon X5200 receiver, paired with a Krell FPB-400cx power amp for the front L/R channels, and my Legacy Audio Signature II speakers, which are from the 1990s. I think you can get some pretty good sound from a package of your current receiver, separate power amp, and a significantly upgraded speaker such as the Expression.
You can always add a higher quality pre-amp later.