"Bombing everything" would work against Byakuren, if Superhuman and LFS weren't in the way. From what I remember, Byakuren doesn't take any extra bomb damage during Superhuman, and LFS is a final card, so yeah. Byakuren took way longer than Shou for me the first time, and I blame those two cards.
Enigma, I believe there's enough tokens to supply 4 large UFOs. A bomb might be needed to summon the second, but at least ReimuB has greater speed when bombing to help collection. If you use that one bomb, you'll have 6.33 for Nue. Speaking of which, I want to say each wave of hers is a randomly-oriented static pattern. Learning how to do them without bombing will help you tremendously against Byakuren (namely, more opportunities to bomb the harder stuff).