It would be very nice to be able to be able to manage profiles more directly. Here are some ideas:
Import/export would be easy since every profile is just a row in sqlite.
Instead of duplication, I'd suggest to have backups to multiple repos in a single profile. Borgmatic does it like this. Of course it would need to fail gracefully if the destination isn't available.
Personally I have 2 HDs for onsite backups (using the same source folders and exclusions). I find myself changing the repo and then running the backup again. It sounds like your use-case is the same.
Instead of duplication, I'd suggest to have backups to multiple repos in a single profile.
That might work just as well, yes. The profile as a starting point is common across other software and might be easier to grasp (I'm thinking of Vorta as a way to get people with no CLI experience to adopt Borg) but doing it in the way that makes most sense from a Borg perspective might be more flexible. Multiple destinations in the same profile would open up some neat possibilities, i.e. back up to every available destination, local or remote.
Personally I have 2 HDs for onsite backups (using the same source folders and exclusions). I find myself changing the repo and then running the backup again. It sounds like your use-case is the same.
Indeed. I did make two profiles and named them accordingly, but all settings including the password are identical.
Then let's start out with multiple repos in one profile. For implementation, the repo-dropdown could have checkboxes, like this:

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Multiple destinations for the same profile would be very useful, indeed. I really hope you can add this feature to Vorta.
Just a little note: having the ability to "clone"/"duplicate" a profile would still be useful when you want to create a new profile similar to an existing one but with few changes, instead of recreating it from scratch.
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Then let's start out with multiple repos in one profile. For implementation, the repo-dropdown could have checkboxes, like this: