I’ve noticed one thing, you have a bit of unused space between brush size and gradient thingy:
How about making there a mini toolbar with most common file operation (new, open, save, save all, export image, export animation)? This would save a click when doing these things.
Create a project with alpha transparency. In that case this space is already used. I have something else in my features list that lets you create your own tool windows by assembling your own functions. The window can then be placed where you want. Once window docking is included then they better integrate overall, so I tend to wait until this is done.
Ah, I see. Sorta like toolbar customization in MS Office, Libre Office, Visual Studio and so on, right? I’ll wait then.