Great idea, I would love to do that, and just may. Last few years I have planted Mint in my front flower bed. I will tell you I love it. And I found that I put mint in more things than ever. Plus, I found my ducks love mint leaves stripped from stalk thrown in their water, they gobble it up. Also I am going to try to put some fresh mint leaves in the chicken nest boxes (saw similar with sage, mint leaves, and parsley on Pinterest), supposed to be good for the girls.
I know people told me, it will take over, but I would rather have mint take over than weeds. Between the garden, the flower bed, the chickens, the kids, and the fruit trees (no particular order, mind you), I would rather wimp out on the flower bed now and take time later (many years later) to fix that up. I still pay some attention to it, but we live back a 1/4 or more mile lane, only the UPS man occasionally sees our front yard or friends/family. So, I am okay with the varigated mint and regular mint taking over my flower bed.
Again, I love the front edible garden. I remember reading a little story of how silly we humans are for tearing out all of the weeds with many uses and flowers and putting grass that needs mowed and has no pretty flowers in it. So true, wish I could remember the little saying I heard, it was much more eloquent that I am being now!