So last night I learned that you're definitely supposed to ride a broom sidesaddle.
For the most obvious reason of course (OW), but also because the handling isn't designed for riding astride. Riding astride means the sensitivity designed for one hand is way too responsive with two hands, and the balance is all off.
So I wobbled all over the sky, desperately trying to keep my broom on an even course towards home, finally managing to get over my house, then putting the broom into what I thought was a shallow descent, only to fall into a steep dive that wound up with the broom driven into the roof and me on the lawn.
Always ride sidesaddle, people. If you want to ride astride, get a bike.