Barring a trade, the team looks like this:
Point guard: Kyle Lowry, Aaron Brooks
Shooting guard: Kevin Martin, Jermaine Taylor
Guard/Forward: Trevor Ariza, Shane Battier
Small Forward: Chase Budinger, Mike Harris
Power Forward: Jordan Hill, Alexander Johnson, Patrick Patterson, Jared Jeffries
Forward/Center: Luis Scola, Chuck Hayes, Brad Miller
Center: Yao Ming, David Andersen
That's two players too many. Alexander Johnson is a long shot to make the team at a crowded position, so that leaves one more that has to go. Jermaine Taylor has talent, but doesn't seem to want to play within a system. He scores points, but the team is not better with him in the game. Jared Jeffries is a journeyman with a star's contract. That makes him hard to move and even harder to eat his contract and waive him. Rookie Patrick Patterson has a promising future and there is no way Morey would give up on him before at least two seasons have passed. David Andersen served his purpose last season as a stopgap for Yao, but he will never be an elite center in the NBA. With five players that can play center, David may be the odd man out.
Is the Rockets' core roster set now? Most all the free agents have signed with other teams. Are there any deals out there that could be made? Sure. Everyone is always looking to make a move. With this team, assuming Yao plays significant minutes, the Rockets will make the playoffs. They will even get to at least the second round. But this is not a championship team. Yet.