Any tweaks I'm missing?

Are you using tube electronics?

Most tweaks are tuning devices--if they actually change the sound, whether the change is an improvement or a decrement, is a matter of taste and the specific implementation in a particular system.  With so many devices, it would be hard for you to even know what these tweaks are doing to the sound.  I think you should start by removing items to see what that does to the sound.  Given the number of devices you have, the possible combinations are essentially endless, but, at least this is a no-cost approach to changing the sound.

In my experience, the biggest changes come from power conditioning/treatment and from using systematic grounding devices and schemes (like the Nordost system).  You don't necessarily need rack space for power treatment, a very good power strip (like those from Isotek) can do quite a bit to improve your system. Power conditioning and grounding devices improve soundstaging and clarify instrumental timbre without dramatically changing tonal balance (meaning sound will almost always be an improvement).  Isolating platforms and feet also change sound a lot, but, because they change tonal balance, the change in that respect can be good or bad.  

By far, the biggest change occurs when you optimize speaker and listening chair placement and do some form of room treatment.  That does not necessarily mean buying exotic traps and panels--it could mean using spot rugs on the floor, tapestries on the wall, movement or addition and subtraction of furnishings. 

Make speaker cable elevators out of Styrofoam cups and masking tape! A cheap tweak, for sure!

Wow. I mean, not bad. I'd go BDR Cones over Vibrapod, try em if you want more a more dynamic presentation. But ..., you asked for additions:

Cable Elevators. Doesn't have to be the brand name stuff. Cable Elevators are really just ceramic insulators. Buy Cable Elevators if you want that particular look and want them to all look exactly the same. Otherwise go on eBay search ceramic insulators, you'll find exact same as Cable Elevators plus a whole bunch more. I've tried and compared, only real difference is dimensions, shape, color, they all work great. Use them under speaker cables, power cords, interconnects. Much more effective than other things like wood, plastic, etc. All of which work. Just nowhere near as well as ceramic.

XLO Test CD- has demagnetizing tracks that really work. There's other CDs with the same idea. Have not compared. XLO, one track is a sweep tone, the other a bass fade. I copied mine onto a CD and duped the tracks so it plays several times while the system warms up. If you've never demagnetized like this let your system warm up, have a good listen, then run the tracks and listen again. The longer its been the greater the improvement. I do mine every week or so, and every time I want it to sound really good.

Radio Shack Bulk Tape Eraser- these used to be readily available for $20, now hard to find and getting up there, but they come up on Amazon. Or any large powerful demagnetizer. Used on records (yes- I report what I hear and leave it to others to explain why it works, or doesn't, it being after all impossible to demagnetize vinyl) and CDs just before play. If used on a CD you may notice the improvement particularly in top end clarity and reduced haze dissipates after a while. But only if you listen real close. I told a friend who hadn't noticed, then said wow you're right. Perfect for records as it lasts just about long enough for a side.

Also works great on cables. Only problem is with cables you have to go slow and the unit gets hot and after thermal shutdown can take 20 min or so to cool and work again. If you get one after a while you'll figure out what you can do and not do to get the most out of it. I do records every side, cables a little less often.

Static Guard anti-static spray. Ordinary laundry anti-static spray. Spray this over your cables and even with zero noticeable static electricity you will hear a cleaner, blacker presentation. Again, the longer between uses the more you notice the improvement.

Okay now for the big guns-

Synergistic PHT, ECT & HFT. PHT come in different versions or flavors. Black Widow is the most neutral safest bet. Green Dream is super liquid, like that one a lot too. I have two GD and one BW on my Conqueror arm. ECT, two of those on the arm base, one on the motor, three on my amp, couple more inside my Herron phono stage. ECT are so amazing I pull the one off my motor stick it on my laptop and movies take on an impressive near 3D quality, like going from 1080i to 4K. 

HFT, HFTX, HFT Wide Angle, Speaker Kit, I have them all. Don't know which is more amazing, the way moving one even an inch makes a difference easy to hear, or that they work at all. Ted's placement suggestions are spot on. Tried others, nowhere near as effective. The upper ones on the front wall, depending on where you put them, you can fine tune the amount of sizzle on cymbals. A tweakers wet dream!