It would be great if all the toolbar buttons would always be visible instead of having to scroll.
EasyMDE does this already:

Related to this, there's a problem with the visibility of scrollbars.
The macOS, iOS and web app all show a vertical scrollbar which doesn't look very nice.
In the desktop macOS app a vertical scrollbar is visible at all times (v3.0.25):

On iOS and the web when scrolling is necessary:

