Gizmo performance in editor is bad, any way to speed things up?

I have about 20 gizmos and my scene view is really slow, is this normal?

It’s hard to say from the code snippet you shared, since I’m guessing most of the magic happens inside DrawArrow.ForGizmo. That said, I would strongly recommend just profiling the editor when you are experiencing this problem, as it will let you pretty quickly pinpoint the source. If you find something in particular that you can’t figure out an alternative for, it would probably merit posting a specific question on this site.