Feature Request "Avoid Gap Fills by changing extrusion width of Perimeter Lines"
A Hint and a Feature Request : The 'white colored' Gap Fills 
often produces a lot of Print Head Movements all over the actual layer height area, only that these tiny volumes are filled.
If you' like to, you should try to disable the Gap Fill :
Set in Print Settings -> Speed -> Speed for Print Movements -> Gap Fill : to 0mm/s.
This will disable all Gap Fill G-Code Generation. Really worth a Try!
E.g. even when printing Lithophanes it has no negativ effect.
My Feature Request :
Instead of a 'separated' Gap Fill, displace the Perimeter Lines closer together,
and calculate a higher extrusion width/rate for these now thicker lines.
I really could believe that this would need high and somehow recursive mathematics
( already calculated perimeter ways have to be re-adjusted, ... ).
RE: Feature Request "Avoid Gap Fills by changing extrusion width of Perimeter Lines"
This is a user to user forum. While the devs do occasionally pop in here its a rare thing. All feature requests and bug reports need to be made over on the Prusa Slicer github page. Located here https://github.com/prusa3d/PrusaSlicer/issues
Although I am pretty sure that such a request has already been made there. After all there are over 1800 open issues.
There you go https://github.com/prusa3d/PrusaSlicer/issues/5591