Steven Universe - What WOULD it take?

not sure. MAYBE (unless proven otherwise later in the show).

then again there's already a fan comic about their reaction

EXACTLY!
she and Steven attempted to run away/elope? not used
bringing a sword home then sneaking off to get said sword back AND kill mutants with it? still not used.

you have to imagine what would it take for Priyanka to finally use THAT.