Neville: I agree with your statement as a whole but is there really a “sfaradi” havara? Iraqis and Syrians are close to one another but not the same; Moroccans and Tunisians are very different from Iraqis and Syrians, Iranian, Bukharian and Afghani pronunciations are similar to one another but are very different from the rest, etc.
Having studied the subject for a bit, it seems to me (for the little that its worth) that Iraqi/Baghdadi is the most authentic and almost everyone else stands equal-distanced, in one form or another, from the Iraqi pronunciation (except the chassishe pronunciation which stands very distant from Iraqi).