To give an honest opinion on this subject.

I accept Jedi as etherial ghosts, and them fading into the ether (transparent)

although.. and this is a bit iffy somehow I don't like the idea of Vader going quite the same way but not that I don't agree with what's left of his physical form should vanish.

I could imagine his head or what's left crumbling to dust almost like going in a similar fashion but not quite the same.

It's a tricky subject to confront such ambiguous mythos but I have to admit I very much like the idea of the empty mechanical husk that is left to be burnt on the pyre.

It's an interesting take not sure if it woould work either vanishing like a Jedi or in another way like I suggested but yes I will say it's a fascinating take on the mythos.

I don't see Vader as fully redeemed just because he threw down the emperor and although a very good deed it still for me does not cancel all of the atrocity so don't mind his ghost showing up either, but should there still be something that singles Vader out as a bit different?

Perhaps Anakin's ghost should only appear momentarily and then fade whilst Yoda and Ben stay visible almost suggesting they brought him along to show luke with their powers a glimpse of his fathers spirit rather than this contrived vision that he has been redeemed for one act of good amongst many bad evil doings. and it was done for Luke not for Anakin.

relegating Anakin to a ghost by removing the blue aura so it would imply he spirit is at peace but he is not a force ghost and had not the means to become one being a sith and all.

I don't know but that is a different way of looking at it I guess

something that is also very important only Luke can see the ghosts nobody else can. And he only sees visitation by force ghosts but if Anakin was shown in commune and un force ghosted it would take on a whole new meaning to the realm of the "Force Ghosts" and create even greater mythos so I think that could be a very good thing in a way..