Beginner money for separate Amp/Preamp for Hm Th

Yeah, there’s not a lot to go on here re: what you’re looking for in terms of sound characteristics that are important to you.  Also, you’d probably be better off figuring out what speakers you’re going to upgrade to (or upgrade speakers first) so you get an amp suited to drive them.  It sucks to find speakers that blow you away only to find that your amp doesn’t work with them sonically and/or functionally. 

That said, just keep the Denon for HT and get a good stereo integrated amp to handle your front L/R speakers.  The 4806 has preamp outs you can use to incorporate the integrated seamlessly right into your HT setup, and it’s super easy to do and lets you completely remove the AVR for critical 2-channel/vinyl listening just by pushing one button (if this sounds too good to be true it is, but it works anyway).  Many of us have done this here when HT and stereo systems had to coexist in one room.  If this sounds like something that’d work in your situation we can go over hookup, but like I said it’s stupid easy.  Anyway...

ditto soix   
Just too lazy to write it out.

I’ve been reading a bit more & a hybrid amp seems to be a great solution.  My Denon’s volume goes into periods were it get louder & almost no volume & very tin sounding.  So, I don’t have the luxury of waiting.  The sound characteristics I like... this is where I say “I like a black background, a sound floor that falls away & a soundstage with exceptional separation.” One of the dumber things I read all over the site bc everybody loves muddied sound that flows together in a congealed mass with blissful background white noisey hiss. lol

I listen mostly to Rock & Blues. I could say I find many systems deficient in midrange & I love the smash of a cymbal full bodied & crisp but, that seems more relevant to speakers.  Does this help?

Here’s what I’d do if I’m you.  I’d get a Yamaha RX-A2070 AVR from accessories4less.com for $1200 and just start there (although the 1070 for $900 may work too depending on your speakers).  Why?  I drove a pair of $9000 B&W804D3s with one using my best 2-channel audiophile demo music, and it was flat out amazing.  The Yammy was clear and neutral and managed to deliver a transparent 3D soundstage none of the Marantz, Denon, or Arcam AVRs could manage, and it actually reminded me a lot of my own much more expensive stereo separates.  In short, pretty much just what you’re looking for.  And in case you’re wondering, the Denon sounded soft, veiled, and flat by comparison (these were all top one or two models for each manufacturer as of early 2020 BTW).

I say start here because you may well like the sound enough to happily stop there for a while until you’re ready to upgrade your speakers and decide on a good integrated then.  Given what you’re looking for a Hegel H190 would be one to look into, but that may be jumping the gun a bit.  Anyway, hope this helps at least somewhat, and best of luck in your search.