The ride height reference is measured from the axle to some arbitrary point above the axle with both wheels suspended, so that number does not change with tire size. Since we ride with the tires on the ground, the actual ride height is dependent on tire radius, not diameter of tire so if you switch to a tire with 5mm less radius you would need to add 5mm ride height to match. Ride height does 2 things to improve agility. raises CG which makes left to right transitions quicker, and secondly decreases the trail that makes turn in quicker. If you go above 20mm ride height you will have too little trail unless you change the triple clamp offset. Unless you want to start making other geometry changes going above 20mm will start creating other problems
GoGo is currently developing an adjustable triple for precisely the reasons you mention. A protype has been made and is currently undergoing testing.
Personally, I often struggle to find setups that make a huge difference to handling, meaning the type that when I go out I think "wow, that's so much better".
That is probably largely due to the fact that I have never been a champion racer that pushes extreme limits, I do push but am always mindful of:
a/ my pride and joy under me b/ my business which would sink without me 12hrs/day and c/ my family.
However, with the adjustable link I did feel an immediate positive difference.
As an aside, a friend of mine has been involved in the MotoGP scene for decades, firstly with HRC and then head hunted by KTM when they started developing their MotoGP bike. He was telling me about testing where they experimented with torque settings on the front engine mount bolts, which, apparently, affect something in the handling. After one lap the rider came back in with the comment "are you trying to kill me". Obviously, the point is that it's the really fast guys that notice the slightest change in setup, the rest of us mere mortals tend to ride around the problems or not even detect them because we are simply not going fast enough. And, let's face it, I doubt that 99% of road riders ever get close to those sort of limits, and the other 1% are temporary lunatics.