Lowry and Burke's game are nothing alike. In the draft you take the best talent. PG is also a very big position of need in Toronto. Burke is on a rookie deal for 4 seasons which means the Raptors would have his rights for up to 8. See how Eric Bledsoe has worked out with the Clippers.
Burke would have to have like crazy workouts to get up in the top 3. I just can't see that happening. He reminds me a lot of D.J. Augustin. When he was coming out of Texas. Good shooter, high ball I.Q. but nothing separate himself physically.