Not really, you may just experience a higher degree of "not greatness."
I have found however, it can cut a little both ways. Several recordings that I thought sounded pretty good went kind of flat while others that had sounded dull took on a new life after I changed gear...
As a wise person wrote above "upgrade at your own risk"
Still, there are many happy surprises...
I just had my amplifier so upgraded that it is essentially new except for the case, and a new pair of speakers so I know what your going through.
Yes, the "room" sound plays a big part but I think you know that already.
I have had many GREAT improvements by doing simple tweaks, like Tip Toes and fuses etc. Try some of those if you haven't already.
There are a ton of inexpensive and DIY solutions that can make a big difference. Don't throw out your amp just yet...
And of course price doesn't equal performance. It's a lot of previewing and seeing if all the gear talks to each other well.
All the best on your search for musical enjoyment!!