Krita has changed so much within the past 2-3 years. Its one of the most easiest program to navigate, rotate, change brush size with, simply by using the drag method (along with pressing one of your pen's button) with your pen and using keys such as ctrl, shift. x (rotate). Best program for work speed (Based on how I set it up) I try to make photoshop behave the same way, but it doesn't let you, same with Medibang (New Main since Krita is more for painting, etc, and Medibang is more for mangas and comics). You can't really fill in a color in correctly, Krita is pretty bad at doing it, but it is great for sketching, painting.
I wish all program adopt the drag method (for pens and tablets) to zoom, rotate, change brush size, opacity, etc. It's just so much better to work with,