The Administrator being able to manged the subscribed user makes sense. This is still the first iteration of the feature and when the team starts work on improving it further, we will keep this feedback in mind.
Hello, I've recorded a video that demonstrate some of the form improvements we've introduced in the 12.1 and the past few releases. I think these covers the majority of your requests.
The export issues will be investigated and fixed.
I actually cannot reproduce the first one on Sitefinity 12.1. The other two are logged for fixing in our system and you can contact the support team if you want to make them public.