Best Bang for the Buck Upgrade

" Bang for the Buck "

B 4 any component upgrade, or speaker replacement ( last resort ), I  suggest that you decouple your speakers from the floor. This will eliminate, or minimize, the vibrations going from speakers into the floor and reflecting back into their cabinents. 

If you do this, it may clean up the sound and tighten the speakers bass. Try using Herbies or Sorbothane pads. I`ve done this, and it was like I had a new pair of speakers.

After decoupling, your sound may benefit from room treatments.

Best bang, $340 Duelund/Mundorf Ultra Loudspeaker Purifiers by Audioman58. 

Biwire?

Tube amp in lieu of hybrid?

It's a 'system' so changing one thing is just a part  of the bang...

Improving your power to the system ( I use and recomend Puritan Audio PSM136 or PSM156) will  upgrade your source and amplification in one swell foop. I have dedicated lines and PSM1136 still made a big difference in timbre, sooundstaging and dynamic impact. As davidten and others recomended, no matter how your audio journey unfolds, getting the power right is foundational.

I knew you were going to say top end and mid bass! It's always the case IDK why, but subs can't fix the midbass and while often recordings are often to blame for the top end I've found after my last round of speakers that a few companies are getting it right. The tweeter in the salon 2 is one, but you would need twice the power for those. The Kef Blades have an amazing tweeter and manage the midbass transition with just a little toe in. I upgraded my speakers after 25 years of being flogged so tbh you will probably get more fun just from moving the system to the long wall and play around. You already have a complimentary system.