A tramway for Oxford sounds like a nice idea, however my opinion is that the city is too small to justify the costs and expenses of building a tram.
What would work best imo is the 400 bus route (Harcourt Hill - Seacourt P&R - Railway Station - City Centre - Oxford Brookes University - Headington - Thornhill P&R - Wheatley) being run by articulated or double articulated trolleybuses like the Van Hool Exquicity or the Solaris Trollino Metrostyle. And then if extra capacity is needed, upgrade to a full tramway.
Excellent bus service by UK standards
Excellent? Hahaha not a chance. Granted, the buses do have amazing liveries and the routes are frequent but the routes are inefficient using completely unsuitable single door buses which unnecessarily increase journey times on busy key city routes like the 1 / city5 (Rail Station - Blackbird Leys), 400 (Harcourt Hill - Wheatley), city 8 (Westgate - Barton) & city X3 (Barton - Abingdon via JR & City). Now before a certain someone who I won't name comes here, I'm not saying all routes in Oxford need dual door buses (the S routes like the S2 and S4 are perfectly fine being single door) but I'm a regular user of Oxford's busy city bus routes and they would certainly benefit from dual doors.
And yes, before you start commenting, I am aware about the Euro 3 Mercedes Citaros (840-847). The problem is that they are single decker and won't work on busy city bus routes. They need to be dual door double deckers - ideally a Scania N280UD ADL Enviro400 City CNG like what Reading and Bristol Metrobus has.
The only pedestrian street is Cornmarket. It is, just, wide enough for two lanes of vehicles (and was horrendous when buses used it in both directions). St Giles is wide enough for trams, but is currently sacred to the parked car. St Aldates copes with buses in both directions, and lots of bus stops. It could not cope with trams and buses.
High Street around Queens Lane bus stops is wide enough to be able to accommodate trams, the problem about Oxford is that the city is too small to justify a network. In fact, by size, I wouldn't even call it a city - much more like a large town!
If anything, Bristol is a city in the UK that absolutely needs a tram network, and is big enough to justify one, seeing that Bristol's population is about roughly 470k unlike Oxford which is just about 150k. Put it simply, Bristol's population is 3 times the size of Oxford, and doesn't even have a tram network, which similar sized cities in the UK like Nottingham or Sheffield do.