Personally, if they were to go-ahead with this, it would make sense if they had started it a year or two back, so that the vehicles could have been presented as part of the 100year celebrations.
That isnt to say they still cant do something with the vehicles though and do some sort of project.

However, I think they should choose a range of stuff going back over a period of time, rather than sticking anything that is too recent.
A photo used to cover the timetables in the mid-80s. Taken outside Gateshead Metro, it showed a huge chunk of the fleet inc ECW Olympians, Nationals, Metrobuses and Atlanteans. Those and some of the more recent disposals (maybe staying away from the Darts, especially Marshall Darts, Marshall Capitals, Plaxton Darts and Carlyle Darts as well as the Wright Handybus) - is it just me who dislikes them?
I cant see anything much older from the early seventies or beyond still surviving if it hasnt been worked on and restored already.

Imagine if they had sorted a load of old vehicles and put them in service as part of the celebrations? An Olympian plying the Coast Road towards North Shields, an Atlantean roaring up Old Durham Road, a VR working from Shields towards Chester, a Metrobus slinking through Low Fell towards Durham, a National ploughing through Washington or a Delta winding its way through Springwell Estate?