This is a bit of a silly idea, but it has potential. Instead of going through all the trouble of mixing up a batch of mead and waiting for it to finish before you find out if the recipe is good, why not make a sample "pseudo-mead"? Just fill a tall glass with water, your chosen honey, and whatever fruit juices/spices you are thinking about, then add some vodka to get the desired alcohol content. As long as you got the proportions right it should come pretty close to the final taste, wouldn't it? I know this is goofy, but seems better to waste a glassful of ingredients than a gallon or five gallons worth. I'm not sure if you could simulate a braggot, and sparkling meads would be tricky, but it seems plausible for most of the rest.