You want to know which series is popular with men and women? Yet again, mother f***ing Senran Kagura. Please enlighten me, Gale. I thought it was anything but. Wrong, betch! Senran Kagura is ninja Sailor Moon with a side of tongue-in-cheek fanservice. It's a lighthearted, story-driven series filled with powerful cute girls, above average gameplay, and action that let's you play dress up. Senran Kagura is also one of the few games that let you play as a badass old lady. It is fun for the whole family.
Now that I have your attention, let me explain why Smash needs this badly and what Senran can provide.
Yumi is an adaptable mascot who already crossed over with Sega, Atlus, Koei Tecmo, Nihon Falcom, Tatsunoko, and Arc System Works. She starred in a third-person shooter, a card battler, a pinball game, a side scrolling action game, a hack and slash, a cooking/rhythm game, and a 2D fighting game. Putting her in Super Smash would be business as usual. That resume sounds like Mario and Pacman. If it was any other character, people would be begging for this to happen.
That's not all. A Marvelous rep could bring in a triumphant clusterf*** of distinctive worlds. Maybe they could bundle her with Harvest Moon, Daemon X Machina, Lord of Magna, and No More Heroes content.
Let's recap. Men and women love Senran Kagura. It's a flagship series for its company, which could bring a lot to Super Smash. A mascot like Yumi is adaptable like Mario since she isn't bound by any genre.
You almost had me, Gale, but what about Cero? We're safe. Senran planned for that s***, too. Look at how fully clothed they are in their uniforms: