I'll certainly vote for the "mass-delete" option; I've got a large project with 40+ unique layouts that I'm going to upgrade to C3 soon. I'd love to import the project just for the layouts, animations, and tilemaps.
Long-term this could be great for access C2 projects without having access to C2 itself (in my case, I've recently switched to a mac, so it's a small ordeal stripping 3rd party plug-ins from c2 projects)/