It would be nice if you could mark shaders as “Keywords not changed by code” so that you don’t have a million varients for no reason at all. The varient generation is extremely painful for something rarely done. I understand the need but making everyone suffer it isn’t nice. It would speed up building as well as make smaller installs by avoiding useless varients. Currently, a simple scene with a terrain and a single tree has thousands of varients. Add a simple cube using the standard shader and you just added thousands more.
I know you can just write your own shaders with no keywords but that is painful for large games. Also changing your mind requires a rewrite of all shaders which could be avoided with a simple checkbox.
This is my largest beef in Unity, even more than all the Editor bugs recently added. Especially since for some odd reason certain shaders rebuild every time even if you don’t touch anything breaking cacheing.