Hi TJ -
Don't sell anything just yet. You have some good components. It would be better to figure out what is it that you want your system to do. You mentioned that you are experiencing some fatigue and are no longer able to listen to your stereo as long as you used to.
That happens to all of us at some time or another and maybe taking some time away from listening to your system may help reset your hearing. I have been going through this for the last several months and am just beginning to get back into listening.
Depending on where you live and what audio stores are available to you, I would suggest auditioning as many different speakers as you can. Speakers will typically be the source of your listening fatigue. You listen to early classical, so you will need to make sure to have the type of music that you like available for your auditions.
Don't be afraid of tubes and tube maintenance. There are brands like Prima Luna that are auto biasing, so it makes owning a tube amplifier as easy as owning a solid state amplifier.
As for what you may or may not know about system basics, speaking to audio sales guys can get you some of this information. There are plenty of YouTube videos out there. Be ok with asking questions.
Rich