One of the prospects I personally like the most for the Rockets with the 14th overall pick is Kansas' Markieff Morris. DraftExpress has put a video together of his strengths as a player that makes for a neat watch if you're not exactly sold on his athleticism.
Watching the tape, Morris reminds me a lot of Mavericks forward Shawn Marion. He has good traits of both a strong power forward (rebounding) and a small forward (quick hands, range on his jumper, lateral mobility) that could translate well to the NBA. He may not be as good as Marion because he's probably not quite as quick, but he's got a broad skillset that should translate well to the NBA.
The Rockets are often linked to Chris Singleton at No. 14, and while Singleton has better perimeter defense than Morris, he also doesn't have anywhere near the offensive game that Morris has at this point. Morris also has improved every year he's been at Kansas, which is a sign that he's still not reached his ceiling yet. Houston probably has a few better options in mind, and could find themselves trading up to get those, but if they're stuck at No. 14, Morris makes a lot of sense for them.