Shader Compilation Time

Hello folks,
I’ve tried search ways of decrease the time necessary for compile shaders at UE4, but unfortunatelly there are very few people who talks anything about it.

In my time using UE4 i’ve noticed huge problems with shader compiler optmization. There are:

-Shaders will recompile for your project if you change the render settings quality (changing effect quality for example from high to normal, and it sometimes recompile again if you switch back from the last one was selected)
-Shaders fully recompile at update of engine version = unreal 4.24 preview 1, it will fully recompile at preview 2, which is exactly the same shader code.
-Shaders compile at identical materials > Could easily be skipped/duplicated asset code to materials that are equal.
-Material will recompile whole instructions even if you change just the parameter default value. (that’s really unoptimized, ideally it would be cool if just the part you changed from the material got compiled instead the whole material, but it’s could be hard to implement, anyway would help alot can change the default parameters values without it recompile the whole material)

I think this little list above already would do a big improvement in compile times.

Could more people suggest and discuss more about such topic? I really feel losing many time just waiting shaders compile even having a good spec PC.
Thanks in advance!