FPS has definitely not improved, quite the opposite in fact. With ORBX TE, ASXP real weather performance textures, and the Aerobask DA-62 I was seeing 30-35 fps flying at around 2000' under 11.26. With 11.30 I'm seeing 25 or so, dropping to less than 20 around London for example. Some of my payware is unusable over the UK, trying to land the FF767 at Heathrow on 15 fps loses it's charm pretty quickly.
With standard scenery away from the UK I see a similar percentage reduction in frames but I'm still mostly around 30 so eminently flyable. I do have problems with my Mega SP scenery, depending on the aircraft it can drop to 20 pretty easily.
Of course I could turn the detail level down one notch, but I didn't pick up the TE and MegaSP scenery to turn off details. Personally I think 11.30 is a disaster of an update, the new particle system is way OTT, ATC talks nicer but is still rubbish, the default cloud textures haven't been touched and quite a few lua scripts no longer work. It looks like Laminar went more for eye candy than any of the improvements that many users on the forums were asking for.
OTOH handling does seem smoother and more realistic.
I nearly kicked my CPU after the 11.30 update because I hadn't reinstalled the ASXP performance cloud set and was looking at 15fps sat on the ground at Biggin