If we're going to persist with the back 5 then Nelson has to come out of it, his distribution is terrible and any manager will just tell his players to make sure he gets the ball when Cardiff try and play out of the back. I think the natural home for Pack is to play in a back 3 at this point in his career. Something like:
Smithies
Ng McGuinness Flint Pack Giles
Ralls Vaulks
Colwill
Moore Davies