I have to revise my former statement about the performance at my rig.
Pre-Patch I played with settings mostly high (except Building details: very low; Trees: Medium, Texture: High; Anti Aliasing 2x; Epilepsiefilter/SSAO/Vsync: OFF) and got reasonable fps with some stutters inbetween.
For example BlackDeath Track test prior to patch installation: 118/41/2
After the Beta I got: 122/48/7, so there was barely a change.
BUT then I decided to just push the details to the Maximum and see what fps I get now just out of curiosity.
And I get nearly the same fps in Black Death: 120/45/4
I can now play with all settings max (except Vsync/Epilepsie/SSAO: OFF; Anti Aliasing 4x) with acceptable fps. Can play some demanding missions with more than 30 planes with an avg of 50. and it looks much better now with more AA und Texture to original
Sure there are still some stutterts as before but right now I'm quite satisfied!