Hmmm, I might have to come back to this one. I have a tendency to use intuition! I know licorice and peppermint are great together, unless you have GERD or acid reflux (peppermint can be an issue there) and I love this tea after dinner as I feel (there's my FEEL intelligence again) that licorice calms and helps with insomnia and lowers blood pressure and I figure the peppermint soothes the tummy after tea so you can sleep better!

St John's wort ... I did hear that whole thing with sun sensitivity was a myth.

And if I'm going to throw a tea together for a cold I'll prob think about what herbs sooth the throat or are antibacterial etc, so I'll look them up as I'm making the mix.

One thing i swear by for migraines is hops and chamomile... Hops can knock your socks off as it's so bitter so for me it makes sense to pair it with chamomile which is so gentle.

Really interesting question!