He should just make the music he wants to. It's Jay-Z for crying out loud. Even if the album appeals to hardcore hip-hop heads, it will still sell what the next guy's whole album sold in its first week.
The only thing I worry about is that Jay has nothing to talk about anymore. These days, he raps about what's going on in his life, so what you get is: "I rolled with the Nets but I still get the net, worth. My net-work is making more than what your nets are worth. Get it?"
He should rap from a different perspective on his next album. It should be a retrospective of his career and he revisits all the decisions he has made. He talks about his upbringing and raps from the perspective from the teenager growing up in Brooklyn pushing weight. Then he moves on to his early rap days, then rap from the P.O.V. of the shiny suit baller (1996-2003), and then rap from his own perspective in the present day. It could just be Jay being reflective about who he used to be and who he has become.