People 100% use KiCad for 6+ layers. My most recent design has 6 and KiCad didn't break a sweat. There's a 12-layer CERN design that ships with KiCad as a demo, even.
No tool has libraries that never need tweaking for a design. 99% of KiCad library parts will never need touching in a usual "simple" design, but no one library part can cover all eventualities. Any tool that promises a library that doesn't ever need to be touched is lying or naive. You should also always check footprints wherever they come from, even if you paid for them.
KiCad has a new library team, and the parts in the library are revolutionarily better then they were say, 5 years ago.
No tool has libraries that never need tweaking for a design. 99% of KiCad library parts will never need touching in a usual "simple" design, but no one library part can cover all eventualities. Any tool that promises a library that doesn't ever need to be touched is lying or naive. You should also always check footprints wherever they come from, even if you paid for them.
KiCad has a new library team, and the parts in the library are revolutionarily better then they were say, 5 years ago.