I haven't experienced any change in performance, and afaik there hasn't been anything i've altered that would affect it, so if you could give a bit more information (including steps to reproduce if possible) that'd be appreciated.
I've got something for ingame performance with carrier ship-system fighter buffs.
Standard Valken wings and Targeting feed seriously degrades performance, even just 3 wings effected is enough to drop my FPS in simulator with only a heron from a steady 60 to 25.
Some other fighter-buff ship systems do absolutely nothing though, for instance Apex Design Collectives Spectrum's 'Remote temporal dampeners' and Dassault Mikoyan's Normadie's 'Strike command' do nothing. Strangely, Magellans Edger's 'Command datalink' doesnt effect performance despite having a very similar visual effect to targeting feed.
This performance hit also applies to Altagrave (C)'s support KARMA and valkens.
Of course, i dont have a potato. AMD ryzen 5 2600 and Radeon RX 580. With all the necessary vram config edits to make modded starsector run, and latest graphics lib. Only other graphics mod is Unknown skies but that wouldnt effect combat.