I think it would be a good idea to have something like this:
Monday, Wednesday, Friday
Lunchtime News: WEST - John Mackay || EAST - Stephen Jardine
Evening: WEST - John and Heather || EAST- Stephen and Louise
Late: WEST - Heather Simpson || EAST: Louise White
Tuesday, Thursday
Lunchtime News: WEST - Stephen Jardine || EAST - John Mackay
Evening: WEST - Stephen and Louise || EAST - John and Heather
Late: WEST - Louise White || EAST - Heather Simpson
Rotating the newsreaders, so that everyone gets to see them at some point in the week.
Just a thought...