On the Democratic side, a New York/ New Jersey ticket would usually be weak. However, Kirsten Gilibrand and Cory Booker would be two young Senators reflecting diversity.
Hillary Clinton / Kirsten Gillebrand
Paul Ryan / Scott Walker
Are you a troll?
Why do you think I'm a troll? Scott Walker and Paul Ryan are both fiscal conservatives who are popular with movement conservatives, both are young, white, and male, and both are from Wisconsin. Meanwhile, Hillary and Kirsten are both prominent Democratic women, both are hawkish, both have big connections to Wall Street, and both are from New York. The Scott Walker and Paul Ryan ticket could put Wisconsin into play for the Republicans while the Clinton/Gillebrand ticket might help reinforce New Jersey and PA if theRepublican's opt for Christ Christie. Both of those tickets represent attempts at amplification in the ticket.
There are constitutional problems with both members of a ticket being from the same state, namely that they can't both win that particular state's electoral votes.
There are some ways around that.
HRC could change her voter registration, just as Dick Cheney went from being a resident of Texas to being a resident of Wyoming.
In 1968, Nixon's residence was in New York but he had the option of switching to California, so he was able to consider Californians and New Yorkers for Veep.
As sitting officeholders, Ryan and Walker are in a different position. Wisconsin would be unlikely to be the state that determines the presidential election, although it might be several points more conservative than the rest of the nation with an entirely cheesehead ticket.
We don't know the legal challenges, or the media response to a ticket consisting of officeholders from one state, so that may be a complication to avoid.