The NZ a team as published can be found here:
http://www.blackcaps.co.nz/display.aspx?pri=36&sec=68&cid=6133&tpl=0
In summary,
James Marshall (Captain)
Neil Broom
Grant Elliott
Gareth Hopkins (wk)
Jamie How
Nathan McCullum
James McMillan
Warren McSkimming
Rob Nicol
Iain O'Brien
Mark Orchard
Michael Papps
Aaron Redmond
Bradley Scott
Craig Cumming and Jesse Ryder were unavailable.
Why they're even wasting their time with James Marshall.... Well, don't get me started, eh!
Of the seven names you mentioned, Flem, Nicol and Broom deserve to be there, Southee is a great prospect, but I think he needs another year before he deserves consideration. Houpapa hasn't really done anything to warrant inclusion in the A team, and Colin de Grandhomme will need to do a LOT more to get ahead of the long queue of middle-order batsman waiting in the wings. I saw him play at the Basin this year, and he looked vaguely okay, certainly nothing special.