One primary reason for the radar page change was that it used flash for single radar animation, which is no longer supported by modern browsers effective a few days ago. I presume the new page is more typical javascript.
Moreover, the new page is designed to look virtually identical on mobile, which is considered best practices. And it's fair to assume most users are familiar with how to use the underlying map controls these days.
I have a similar radar page for the CASA network, albeit google maps based, with a composite page as default for situational awareness and the ability to drill down to single radars. It's pretty tricky to integrate all sorts of product menus, animation controls, zoom, opacity, etc., etc without getting clunky and overwhelming. I feel most sites for models or radars are definitely too much. A side panel with a million options is ok for power users but not so much for the masses. I think Levi has done a really good job with that balance on his page and it would be cool if he could be brought in to help with V2 of the new page. Or just bring radars into TT and rename it weather.data.gov