/bant/'s waifu wars are pretty weak. You seem a bit misinformed, so I'll give you a quick rundown.
Cirno is not a waifu. If anyone considers her a waifu, she is an inferior waifu by default because she is not waifu material. She's just cute.
Chino is so cute. This does not single-handedly make her superior waifu material. She's basic bitch loli waifu material.
Slutania is a shit tier meme waifu. She still has some stragglers but she's a seasonal waifu who has persisted past her expiry about a year ago. Not high tier at all.