Would it be useful to add a CheckboxSet (like RadioSet) widget?

[Alphix]

I've written a CheckboxSet widget based on the RadioSet widget, pretty much the same thing, but with checkboxes instead. This allows the user to tab to the CheckboxSet, use the arrow keys to make a quick selection of a couple of checkboxes and then tab to the next logical form field in a wider form.

Would something like this be generally useful (i.e. should I submit a PR) or is it a niche thing?

Here's an example of what it currently looks like (this is a modal window with a Label, a CheckboxSet wrapped in a VerticalScroll and some Buttons):