A nice feature of a lot of editors is to show available commands when the user has typed an incomplete keybinding. For example, qutebrowser will show available hint commands after pressing the hint key prefix. This would be nice for quickmarks and any prefix keys for new users or if you've just forgotten a specific keybinding.
:set modeindicatorshowkeys true should do what you want I think
This does include that functionality (keys that have already been typed are highlighted in a different color in qutebrowser's popup), but additionally there is a popup showing available keybindings. Here's an example image of the popup from qutebrowser:

Related: #1120 / #1618.
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This does include that functionality (keys that have already been typed are highlighted in a different color in qutebrowser's popup), but additionally there is a popup showing available keybindings. Here's an example image of the popup from qutebrowser:
