However, there were some comments in the PR discussion that this issue addresses. And also there are some other comments from Ivan Masár that pointed them out to me during a dev meeting.
I paste all the comments here:
1) SAF upload from URL is nice, but much more useful would be SAF upload from a local file.
2) The UI for state of import is great, but its location in Submissions is a bit counter-intuitive. It would be nice to have a collapsible (dynamically loaded) list of links to imported items.
3) IRC discussion
[23:14] <helix84> the thing is when you finish import, there's no indication you can go to Submissions (a different place) to check its progress. IIRC>
[23:14] <kstamatis> So, the batch imports appear in the same way, under the exports
[23:14] <helix84> I'll take a look, maybe I don't remember it correctly.
[23:15] <kstamatis> OK, I keep that we need to add a message where to look
[23:15] <helix84> ideally a link