next step please

FWIW, my suggestion to you is to very carefully think out where you want this process to end - long range. Then start identifying the components (or types of commponents) that would fit into that system, and buy them as you can afford them. As it is now you will be endlessly upgrading to no end and will spend a lot of unnecessary money.

A nice, useful response from Newbee and I agree with it. You need to find out where you want to go. The best way to start this is to listen to some very good systems and make notes on what you like about them. Don't worry about the usual audiophile vocabulary if you're not comfortable with it--it's your feeling reactions to the music which count the most.

Once your ideas have coalesced a bit, start listening in your price range for components which give as much as possible of what you liked about the big boys. There are two rules of thumb which I always go by. First,small upgrades don't make it. They cost a lot in the long run and tend to make marginal improvements, sometimes only differences.

(N.B this is *not* true if you have a toxic or broken component somewhere. When a friend showed me how bad my speaker cables were a few years ago, I retired them for fifty bucks' worth of Audioquest Type 2 until I found the ones I wanted.)

Second rule: the source rules. Upgrade starting upstream. A $3K source with $400 worth of electronics will keep you happy much longer than the reverse.

That said, I would guess from looking at your list that the Denon is the weakest point, as you suggest. Your speakers are some of the best you can get at the price and the Rotel player is decent. A really good preamp (read: a worthwhile purchase) and its interconnect will not be in your price range just now. If I were you I would go for a good integrated amp.

I pretty much agree with both above posts, get a plan down with a long term goal in mind, your post is vague as to your goals. Remember that most good gear lasts and sounds good for a very long time, the (latest greatest) is often times a lot of hype when dealing with many of the componets that make up a good audio system. Many times here on audiogon you see a system post, where the owner has taken many years to put a very fine system together, there is no reason you can not do the same. Vague goals=Vague system every time.