I think the special ban really goes for living Elves, and thus Galadriel gets singled out.
As noted, an Ef must be purged in Mandos before returning to physical life anyway; while this is not a ban it still speaks to something like what Galadriel had to overcome as a living Elf. A self reflective, spiritual life in Mandos is arguably notably different that the physical life of the living, and her special ban makes it so that she cannot return into the West without a changed heart and mind.
In my opinion the 'leadership aspect' is how the chief actors (in the letter) were defined.
So the way I see it (ahem so far today)...general ban on the Noldorin Exiles
lifted after Fall of Morgoth. Any Exiles who died before this were normally not allowed physically in Aman in any case, but after the Ban was lifted, those who were 'purged' (and all that) in Mandos could return, in general. Could a purged Finrod return before the ban was lifted? Possibly. Tolkien seems to allow Glorfindel as an exception.*special ban on leaders
Galadriel happens to be a leader who lived. Again I think this ban really only served the living, as any living leader could have returned to Aman without a change of heart. As noted, already dead leaders had the constraints of bodily restoration on them in any case -- they must repent and so on.*Glorfindel restored before the general ban was lifted
I feel like I'm missing something here. Glorfindel died relatively late in the First Age... yes Tolkien desired that he be Glorfindel of Imladris, but that doesn't mean he had to be restored in the body before
the general ban was lifted.
In other words, why did JRRT feel the need to explain Glorfindel as an exception before the ban was lifted, when the lifting of the general ban was coming 'soon enough', especially as Glorfindel had plenty of time to get back to Middle-earth if he simply awaited his bodily restoration.
Or is there something right in front of me that I'm not seeing? Have I already posted about this before? Hmm. Maybe the Eressean question (the question of whether or not the Exiles were allowed to dwell 'permanently' in Valinor after the general ban was lifted) is involved? But still Glorfindel could have been restored upon Eressea after
the ban was lifted, and sailed back to Middle-earth in plenty of time to do the things he is said to do in the already published tale or Appendices.