Tbh, the banning phase in normals and RGMs should be after the second rotation
People ban the same champions 95% of the time, which sort of defeats the point of a banphase. There can't be a champion so broken you can't pick against them. Not to mention, it's, you know, normals.
Team A FP - Team B 2nd and 3rd pick - Banphase sound like it would lead to more dynamic draft. Some people will prioritize what they want to practice, some will pick what they consider fun, some will pick perceived OP champion, some will counterpick those. Otherwise, you might as well disable high ban rate champions and skip it entirely.
Never mind champions are banned for the stupidest reasons. "I'm going to ban
because I don't want people to get practice in on them. Or I'm going to ban

because on the off chance they get fed early and main the champion, they'll pop off."
But let's be honest, the main reason is that people don't know what to ban, since League basically has no specific champion counters.