I suggest the implementation of "INERTIA" settings in both "Affinity DESIGNER"(especially) and "Affinity PHOTO";Alike you can change the behavior of tools in Artrage. so your curves etc. smooth out while you draw. Just like you would apply more pressure to the tool, which would normally have the effect in reality of not being able to move so fast. (Would be much easier to draw specific curves...(sry4myenglish)