So I've done half my job and found some interesting things, Sinizter.
This page from the fusion 101 forum, viewtopic.php?f=6&t=7095&start=20
has a post about two thirds down from Ronin that has some interesting stuff on what levels to use when fusing (see his oiled leather example).
So far I've not seen much on how to get mythical but my brain is hurting and it's bed time, so I'll look again later; thinking it will be later on in the thread.
Most interesting thing I've taken away is the CF = E problem of either not being able to make commons due to mastery OR an apparent stupidly high price for commons on the market due to more people getting on the fusing bandwagon (dunno how true this is). You probably knew this already and it seems obvious now I've read it but we can convert goods to commons for free by trading on city request.
I still don't get how C+F = E works (like I said, brain hurting) but I'm gonna try it and see.