Not to mention the fact that this appears to be just an idea at present; I would imagine that the selection of the presenters would be the last in the list of priorities?
The research document I have in front of me says explicitly: "ITV are considering extending the ITV1 Lunchtime News by half and hour, making it an hour-long programme from 12.30pm until 1.30pm, presented by Nicholas Owen and Katie Derham."
It goes on to ask detailed questions about the suitablility of the Owen/Derham partnership, amongst many other aspects of the extended programme.
And how would an extended Lunchtime News affect the rest of ITV's alloted hours for news?
Good question - ditching the Morning News maybe?