If he is seriously considering leaving, then of course he would absolutely consider the Nets. Why wouldn't he?
If I were in his shoes and he considers leaving, I would think Brooklyn would be a more attractive choice. They're a team trending upward with a good coach and a decent young core. They've also recovered very well after their disastrous trade with the Celts back in 2013. The Knicks on the other hand are doing nothing more than living on a prayer with their cap space and hopes of getting the #1 pick.
That said, the ideal scenario is Kyrie stays in Boston and we get Davis.
Come to think of it, I would love nothing more than if Kyrie stays in Boston (with a Davis trade in tow), Durant and Kawhi go to the Clippers, Kemba signs with Dallas and both the Knicks and Lakers are left with nothing.