[Libreoffice] (Feature Request) Shortcuts for Formatting Templates

The issue was first raised in #documentfoundation on irc.freenode.net;
I would like to forward it here, as I am not involved in development
myself but can see how this feature would improve usability:

The original question was
"Is there any way to customize the selections for the borders on the toolbar?
I need to easily add a double-underline bottom border to cells, and
the only way I can do it now is by going to the format cell box and
adding the border manually everytime."

I suggested to use formatting templates, which can easily be accessed
by hitting F11, followed by a double-click on the appropriate
template.

This is a slight improvement over formatting each cell on its own but
it could still be done a little faster by...

a) adding keyboard shortcuts for applying formatting templates to the
selected cell(s)
or
b) having the possibility of adding icons/text buttons to the toolbar.

here's my thoughts on these options:

Option a) only needs another entry in the formatting templates'
context menu, "keyboard shortcut" and interaction with LibreOffice's
or system-wide keyboard shortcut system.

Option b) might be doable using text buttons (maybe with user-defined
text? after all, the user needs to know what the custom button is
for...), icons would be a bit of a challenge: I do not expect
LibreOffice's graphics experts to come up with icons for each and
every cell formatting option or combination of those...

...greetings.
Niklas