You said "I like the look of a more traditional box type speaker rather than towers or some of the oddball looking stuff that is favored by many. My room is about 15' x 20' with carpet and a 10 foot ceiling. Rock and Roll and bluegrass are my main choices in music. I like to feel the bass as well as hear it."
"what are some good "disappearing" speakers? I am hoping to stay under $2k."
New to newer big Harbeth and Spender Classics for under $2K that will do lots of bass is going to be tough. The older classic "monkey coffins" like the big Spenders, Harbeths, old JBL's, etc. had many great attributes, but were not necessarily known for their tendencies to "disappear".
Thus, we see the rise in popularity of the small stand mount speakers and the now omnipresent slender yet deep tower speakers. The ultimate disappearing act in this price range usually means a small stand mounted monitor - new or used - and usually means trading the deepest bass for imaging (except, see Totem Mani described earlier in thread).
Two ways I can see your money "disappearing".
1) Quality budget stand mount monitor plus good sub for under $2K
Traditional looking Used Monitors for around a grand - something used like Paradigm Reference Signature, one of the British mini monitors in the BBC LS3/5x mold, various older designs by ProAc like the Response One or Tablette 2000, the Dynaudio Contour 1.3 Mk.II or Dynaudio Audience 52SE, Revel Performa M22, Silverline Reference s15, or Totem Model 1. Maybe other people have other suggestions...
New Monitors for around a grand - consider the B&W CM1, Epos M12i, Focal Chorus 807V, Paradigm Reference Studio/20, PSB Imagine B, or Totem Rainmaker.
For Subwoofers around a grand (don't skimp here) - I would look at any of the larger and more powerful subs used (or new) from REL, Hsu, SVS or Paradigm that fit your budget.
2) Or, if you would consider it, a medium to smallish tower speaker for under $2K could fit your bill
Used Towers for around two grand - consider anything from ProAc available in this price range, Revel Performa F32, Spender S8e, Totem Forest (great bass, will do rock but happier playing bluegrass), Vandersteen 3A (this may be too unconventional looking for you).
New Towers for around two grand - consider B&W CM7, Epos M16i, PSB Imagine T, Quad 22L.2, Revel Concerta F12, Totem Sttaf, Vandersteen 2Ce Signature II (this may also be too weird looking for you).
Anyway, you have a great amp. FWIW, my favorite speaker combination's with that unit have been the B&W CM7, Revel Performa M22, Totem Arro and Rainmaker. Good luck in your search.