I can’t remember where I saw it, but I once read that the city was potentially going to name N Broad St the “Avenue of the Sciences”; what a great idea! To also call it “Avenue of the Arts” (like S Broad St) I think would not only be a wasted marketing opportunity, but it would dilute the brand for S Broad St.
Although there are places along N Broad St that would support the AOTA brand (i.e. PA Ballet, PAFA, etc.), there are also important institutions promoting science (i.e. Wagner Institute, Temple University, etc.).
The Uptown project should be great for N Broad St, but I personally believe the science route works better from a branding perspective.