Does an upgrade make sense?

+1 for DAC first.  Then Roon ... I love it and it takes your streaming experience and music discovery to a whole other level.

I may be coming down with the upgrade bug, and I’m open to suggestions. I’m quite happy with what I have—excellent imaging, musicality, dynamics.

Listen to yourself first....😊

I recommend no upgrading before optimizing mechanical and electrical and especially acoustical embeddings...

Dac upgrade if you are happy with your actual dac will be a marginal upgrade compared to what i suggested...

Audiophile experience is more about the embeddings controls than about upgrading a component if you are happy with your actual synergy...

Dont upgrade by changing a piece ; improve all the system/room ... Electrical noise floor decrease controls, vibrations controls for components and acoustical better controls of the speakers room relation ..

Instead of nourishing the upgrading virus disease and the gear purchase spree i will encourage learning about mechanical electrical and acoustical control FIRST and LAST ... 😊

There will be always someone after the enumeration of your piece component to point to some lack that can be compensate by buying a new gear component, preferably the gear the adviser like 😁... If you are happy it is an error to go after an upgrade advice... learn about acoustics, vibration controls and electrical noise floor... Dont buy anything BEFORE ...

Why?

Because you will end with more upgrading tentations and less taste for the hard  knowledge to gain  about the fundamentals which are not in the manual user of a new piece of gear at all... 😁😊

It is my advice for all...

I don’t feel a lack of bass but I understand what they can do to free up my speakers.  But I don’t like crossovers either. 

Understood, but subs will do much more than just add bass, and as I mentioned earlier your entire soundstage will expand in all directions and imaging will also improve significantly obviously as will overall dynamics — all of which you were looking to improve as I recall.  It’s one of those things that once you hear your system with a couple dialed-in subs you won’t wanna listen without them anymore because everything shrinks down and becomes less dynamic.  Last, the SVS subs can be run with speaker-level inputs so no crossover involved if that’s your preference, but you can try it both ways to see which you ultimately prefer.  Anyway, just wanted to fill in a little more info in case it’s helpful. 

Subs are rarely a bad idea, and are usually well received.  

It looks like you've picked most of the low hanging fruit, but assuming your speakers are well designed with good quality drivers, but built to a price point, it's very possible the crossover components are ripe for an upgrade.  Upgrading the caps and cheap cast resistors to non-inductive wire wound types can be fairly easy, fairly cheap, and fairly audible.  It won't change the overall character of the speaker, but could definitely improve clarity (and things associated with that....ie: soundstage, etc.)

Assuming you've done what you can, or are willing, to address room acoustic then I also would say a DAC should be your next consideration. And I'd look at spending as much as you can, I don't think a <$1000 DAC is going to make much difference but maybe some used options.