There would need to be some very expensive land purchase and earth moving to be done before the approach to either RW could be better than Cat1...
The Brize village to Bampton road, the old Bampton road railway bridge and Lew Hill on the approach to RW25 as well as the well-known glideslope characteristics on RW07 pretty well rule out any change to the current situation.
RW07 (or 08 as was) had a 3.24° GS and was not approved for 'coupled' approaches - is that still the case?