"Shoot First" isn't a term to describe a selfish player its just a method of categorizing different types of offensive players. Derrick Rose scores more often than he facilitates because that's his role on his team, he's the number one scoring option so naturally that would make him a "Shoot First" point guard. It's also worth mentioning that even as a "Shoot First" point guard he can still lead a team, Michael Jordan proved that scoring leaders can still be leaders and there isn't a shortage of players who agree with that mentality.
Based on the similarties in both players game (Mid-Range to Around the basket scoring) I think its fair to say that Rajon Rondo is basically the "Pass First" version of Derrick Rose, then again Rondo has 3 Hall of Famers on his team to whom he can pass. This is not to say that either player is better than the other at any particular facet but rather what their roles are on their respective teams.
Here's a couple of examples that may give you a better idea of who belongs in each category
Pass First -
Shoot First -
In fairness the traditional "Pass First" point guard is really scarce these days and this is NOT because players became more selfish but because more and more players are really breaking the mold and creating hybrid versions of both parties.
When you really look at the intricacies of all of these players you can easily make distinguishable differences between Derrick Rose and Steve Nash or Derrick Rose and Deron Williams, but this isn't to say that Rose won't change now that he has someone like Boozer who he can really depend on to shoulder the scoring. However, as of right now Derrick Rose defines what it means to be a "Shoot First" Point Guard, he scores because his team needs him to score.
I hope this could help you a little bit. I also acknowledge that Derrick Rose is a great player and if he had the supporting cast (Maybe he will this year) then he definitely could be a "Pass First" Point Guard, but right now they need him to score.