Basically, Northumberland is just too large. Some council functions need to be more local, so current proposals are that the unitary authority will be subdivided into three 'characteristic communities' [horrible term] which will have their own Development Control, Licensing and Area Committees - drawn from the 20-25 councillors representing that area.
These are likely to be i) North Northumberland (Alnwick & Berwick districts) ii) SE Northumberland (Blyth Valley, Wansbeck and the coast up to Amble) and iii) West Northumberland (Tynedale and the rest of Castle Morpeth). The main points of contention are a) several but not all of the coastal villages want to be linked to Morpeth (or Alnwick) not SE Northumberland b) whether Morpeth fits better with Tynedale or Alnwick & Berwick. I'm afraid this latter point has dwindled into a political argument with the LibDems wanting Morpeth in their northern stronghold and the Tories wanting Morpeth as part of their Tynedale stronghold.
Personally - I think Morpeth and parts of Tynedale look more to the Tyne & Wear city-region for employment, shopping, housing market and leisure and should be in a separate characteristic community reflecting this. Failing this - I guess the West Northumberland community is next nearest.
Then, there'll also be around 26 'belonging communities' [even more horrible term] - generally a cluster of 4-7 parishes, with a community forum including the 2-3 councillors representing that area, possibly representatives from the parish councils, and unelected 'community & voluntary sector' reps. These will mainly be advisory 'sounding boards' for the local councils - at least at first.
Overall - I think the new unitary will be hardpushed just to deliver its statutory functions for the first 4-5 years - and it'll be a chance for those who argue that we'd be better off without 'continual council interference' to test their argument.