Where should I Go Next?

To those who suggest a speaker upgrade, what would you recommend? It won't come soon but advice is always appreciated.

Have you sound treated your listening space with scatter and/or diffusion plates? They’ll improve whatever your intended sonic endgame and are portable.

I do have quite a few diffusion plates...as many as my wife will put up with. Some on the wall behind the speakers and some on the back wall behind my listening chair.

The side walls are pretty far away from the listening space due to the layout of the room.

your speakers don't have weaknesses so it would not be simple to upgrade. Still they are definitely your weak link. (Yeah, contradicting sentences.)

I'd say if your budget was ~3K, used, you would have a few amazing options. 

It would be really helpful to see your system and venue. There is a place under your ID to put your virtual system. It is easy to put photos. This can be really helpful for us to identify places to help. Frequently great gains can be by moving equipment and / or acoustic treatments. 

You can see my systems under my UserID.