Question: If I were to submit an enhancement request bugzilla on
this, would it likely get
done (preferably in time for Fedora 28)?
If yes, then
Question: Which bugzilla (or other tracking system) should I use (please provide url)?
There would be no action taken on any fedora bugzilla you submit on this issue since it
isn't a "fedora" issue. It is related to the rpmfusion packages.
Since you did see the slowly blinking cursor on the reboot could have opened a console
window to check the progress. Also, if you have a disk activity light you should have
seen activity.
I guess, you could always file a bugzilla on rpmfusion asking for akmod to display a
message when rebuilding nVidia drivers. I have no idea how easy that would be for them to
implement.