Krita has a highly customizable UI. However, Default UI is pretty unfriendly towards newbies to Krita. Current Default UI should be judged to be poor rather than simple, so we should add more contents to our default UI. I tried making a draft of a new default workspace and toolbar. My draft is inspired Paint tool SAI and FireAlpaca...
The new UI is roughly divided in four sections: Color, Tools, Brushes and Layer&Navigator
I newly added the following contents to the new UI.
Toolbar: Showing File Toolbar by Default, and added Export, Undo and Redo
Docker: Remove Specific Color Selector and Color Slider, and added Palette, Brush Preset History, Navigator and Undo History