Seems like a good idea to me - although it makes more sense to me, UI-wise, to duplicate the way the Glyphs menu works instead:

The way to make a feature request is to post it over at indesign.uservoice.com. Then, if you want that feature request to be filled, it helps to promote it elsewhere so that people upvote it at the Uservoice, demonstrating to the dev team that e.g. The People Want Bigger Glyphs.
If you do make an official feature request, come back to your thread here and post it! I think that there's a lot more traffic here, increasing the chances that your suggestion gets more eyes on it.