On a whim, I decided to see if my bungs would fit the gallon jugs my apple juice comes in. They do. This means I need more and more airlocks, so I can do gallon-sized recipes for experimentation. Reading on the reddit mead forum, folks have had success with cherry juice and blueberry juice as a base. Think I'll try a blueberry/cherry recipe and if it's not awful/is good, give it away to an LEO on here.
Many ideas for trying things that I did not want to attempt in 5 gal batches, due to potentially being gross. This is no longer a concern. Let the experiments commence!