FWIW I don't think there is salary cap pressure, I think Port has just evaluated its list and realised it's not going to get them to the promised land, and that perhaps 2014 was the anomaly, not 2015. It would not surprise me if more players were available, it's just Hartlett is the obvious name as his output doesn't match his talent, but he still has the aura as someone who could be elite in the right system.
We apparently offered two first rounders last year, and Port said no presumably as they thought they had the list to get back to deep finals.
I don't believe that North offered 2 first rounders maybe the pick you used on Anderson, what you are saying is hovering around the truth but not quite there. It has been reported that there are 13 players on the table if the right offer materialised. There are a few issues that conspire to make this the time to restructure our personel a bit.