You're not crazy. I have gone from bike to scooter to bike to scooter many times over the past 20 years. Whatever makes you happy, go for it.
My buddy has a BMW like yours and a Vespa GT300. Here's a pic of the Vespa.
I like vintage myself.
Here is one of my rides, an '82 Passport.
And this is a barn find I picked up recently for $400. Runs beautifully. Aero 80.
I love scoots and will always have at least one.