Some barristers tend to be somewhat Donnish (Mr Dove is an example of such a barrister), but I would be a useless scholar at any university, because I have no original thoughts about anything. These days just being a good teacher of undergraduates isn't enough, because the publication machine must be kept turning. I have found an OK job using the law as a practical toolkit for the resolution of problems brought to me by clients.
The OP, meanwhile, has to interact with actual Oxford law tutors. Good luck with your collections and/or Mods and/or Schools, OP.
As for administrative law, here is a practitioner's perspective: Much of what the practical lawyer needs to know may be found in Lord Diplock's speech in the GCHQ case. There is no harm in knowing Miller 2 quite well, and also Anisminic. Otherwise, read Wade, or de Smith, but not Fordham.
Arguably, there is only one juridical principle which underpins judicial review: and that is ultra vires. No public body has the power to do anything not given to it by statute or the common law, and no public body has the lawful power to be unreasonable or unfair. Thus Wednesbury, and procedural fairness, are merely expressions of the vires principle. Proportionality is probably just a facet of Wednesbury, but in practice it makes no difference whether it is or not.
The recent Shamima Begum case explains the narrow limits of judicial review. The Court of Appeal evidently thought that the Secretary of State was harsh and wrong to render Begum Stateless after she had been groomed, radicalised, trafficked, and raped; but the Court could not find that the Secretary of State's view was irrational, and the Court cannot substitute its own view for that of the office holder appointed by Parliament to make the decision.
The basic rule of public law is: the Government is not supposed to muck about. The Government often mucks about.