I think you have it backwards. An ordinariate is essentially a diocese. A personal prelature has to work with the permission of the local bishop.
Here is the definition of the personal prelature
http://www.vatican.va/archive/ENG1104/__P10.HTMCan. 295 §1. The statutes established by the Apostolic See govern a personal prelature, and a prelate presides offer it as the proper ordinary; he has the right to erect a national or international seminary and even to incardinate students and promote them to orders under title of service to the prelature.
Their approved statutes control the relationship to the local ordinaries
The ordinariate as previously used term meant the 'organization' of the ordinary.
http://www.newadvent.org/cathen/11284a.htm This concept certainly does not apply to this case the bishops will keep their our organizations.
This ordinariates represent a new concept, with the closest analogy of the military ordinariates, which had some independence, but also strict subordination of the local ordinaries. This is only analogy, because the clerics of the military ordinariates were incardinated to individual dioceses and appointed from there to the military service, so they had personal dependence on the dioceses.
When the Easter Catholics united with the Roman Church they kept their independence, but for centuries belonged to certain Catholic dioceses as separate organizations, and their groups get the rank of diocese only after 300 years later. The reason mainly was the (national) differences between the Easter Catholic units (Hungarian, Polish, later Romanian, Ukrainian)
For the Anglicans now also the legal problem for making them one independent unit lays in their internal differences, first they should agree between themselves.