A vision for a Tablet-enabled, student-centric classroom is one which recognizes and enhances the existing classroom ICT infrastructure, and which then extends this.
Many if not most classrooms already have a Data Projector connected to an existing 'teacher computer' (this latter may be a Deskop or Laptop, Windows or Mac or Linux).
Further many of these 'teacher computers' are connected to an existing Interactive Whiteboard (or there may be a Projector with an 'Interactive Projector')
Many schools and teachers have invested greatly in developing their professional practice and resource bank.
I do not envisage discarding this equipment in favour of a 'new model'.
Rather, I suggest adding Tablets into the environment. These Tablets are for Student Use in classroom where the learning is managed by the Teacher. The Teacher may, in addition, have his/her own Tablet in order to model best practice.
Tablets may be used in a one-to-one ratio or with a Tablet shared among a Group: the former model is often useful for the 'drill and practice' type activities (where individual activity and reinforcement is useful) or for a 'flipped classroom' (wikipedia link) while the latter may suit a Research approach with Group Reporting and/or Group Presentation.
When the time comes to change the hardware (such as continued failing of Projector Bulbs and/or lack of response from the IWB and/or continued losing of a dedicated Stylus etc.)...
...it may then be an opportune time to consider opting instead for an Interactive Panel - with all of the 'real-estate' display space (but better clarity) than an IWB ...and a giant Android Tablet as well!
But please remember to have pedagogy and the student/learner always at the heart of the process!