Touch bar / shortcut creator

Love drawing in miro - and the way its instantly generated across all devices to all users is great. 

What would take it to the next level is to have a little shortcut bar (like notability, apple notes etc) that you can quickly switch between tools (pen, eraser, highlighter etc) and also the ability to set shortcuts such as two finger tap to undo the last action. 

To expand on this - having the ability to set the eraser to pixel erase, rather than erase a whole line / element