I think Mikal Bridges is a safe pick. He's practically Trevor Ariza right now--he'll defend multiple positions, be an above-average shooter on the wing and fill the lanes. He'll fit into the rotation of virtually any team.
However, if you compare Mikal Bridges' freshman and sophomore seasons to what guys like Troy Brown, Zhaire Smith and Lonnie Walker did as freshmen (not considering that Bridges was a red-shirt), you might conclude that these other guys have equal or higher ceilings. These younger players have weaknesses, but they have time to address them and might ultimately have a steeper development curve.
So the question is -- where does Mikal Bridges develop from here? Can he add more of an off-the-dribble game? Can he learn to initiate? Can he add strength and score in the post? Can he add a floater? Etc. He certainly can do these things if he'll work hard.
Troy Brown's ability to play on the ball, initiate offense as a secondary handler, along with his above-average rebounding for a player his size and age, make him a more intriguing prospect to me than Bridges. Brown is only 19. What if he gets to 6'8" and about 225 lbs with a 7-foot wingspan, while maintaining his ability to handle and drive the ball? What if he gets his 3-pt shooting up to 36% in a couple years? That's a solid player.
It comes down to teams' appetite for risk and whether they can project a player to put in the work to reach their ceiling.