Ever since Photon was made mandatory, I noticed a serious degradation in responsiveness of the UI. After I gate jump and start a warp, it takes a noticeable amount of time now before I can reliably F1,F2 my Cloak and prop mod. More often than not, neither activate after I started the warp (even though the server reliably registered the warp because the anomaly notification window appears right away) and I have to press F1, F2 again.
Similarly, the Start button in the industry window is also much less reliable and much slower to recognize clicks. In the past with the old UI, I could reliably start 2 jobs from BPOs within 1 tick. Now it is a lottery to see whether the game recognized 1, 2 or 3 jobs.
Photon was lauded as improvement for the UI performance but so far I have not experienced any better performance. Quite the contrary, the performance has gotten worse in many areas.