Does an upgrade make sense?

Today I think even one of those Bowers & Wilkins DB3D can be perhaps one of the most successful additions to nearly any system with monitor speakers, because it's extremely tight, fast and powerful. I do consider this model the most coherent with nearly any monitor speakers. You are adding to your 1kw another 1kw into the game. Not sure about budget, but one of them would already change game for starters. 

Luv your belz they're real deal.

I suggest you look to find a company who rents Herman Miller panels in your area. Try setting up a few of them to isolate your listening space. I'm a custom furniture maker and am focusing on bespoke audio cabinets and attractive isolation panels. If this approach makes sense, feel free to reach out to me. My firm (madronetimbre.com) will be formally launching online before the end of the year.

Like your clothes, you can change every single part of your system from source to speakers and everything in between.  It helps to know what exactly it is that currently dissatisfies you.  If you don’t like the way your shirt looks on you in the mirror, changing your socks, while potentially an improvement in itself, won’t solve anything 

  And then there is system synergy.  Adding a really fabulous sport coat may show up the inadequacy of the cargo pants.  Getting a killer DAC , for example, that is leagues above the the rest of the system will be bound to trigger the desire to bring everything else up to snuff.  This may be a rabbit hole.  Now plunging into that hole can be fun, obsessive, expensive, frustrating, sometimes all at the same time.  We all need hobbies, but be aware of the pitfalls before you leap.

  It helps to know the end point.  You sound content but bored with your present system.  It is ok to want to make a change, but have an idea of why before you leap

Exactly... Well said in one sentence...

It helps to know the end point.  You sound content but bored with your present system.  It is ok to want to make a change, but have an idea of why before you leap

It is useless and illusory to make an upgrade if we dont know exactly why and how...

And even in this case we must learn how to minimally embed our system before...

A 36'x36' square room is your biggest issue to tackle. Not sure what the solution is but this will always be a tough room to get maximum audio quality in. Definitely work on any acoustic treatment recommendations first before moving on to equipment upgrades. Seeking the help of an acoustic professional would be your best investment at this point IMO.