Hi Patrick,
the standard case in the Marketing Activities is to clone whole Programs. So a webinar registration program which Breno mentioned contains a form, landing pages, emails, maybe Smart Campaigns and can also be configured with Tokens (for the program).
When you have a new Webinar you clone the program and modify information like date, topics, speaker, etc
But if you need and want to you can also clone and move single Forms.
Design Studio is for Templates and (maybe) a standard contact us page. When you want to sendout stuff and want to create whole campaigns you need to use Marketing Activities. So it's not about flexibility, it's about the usecase.
Best regards
Steffen