I'm assuming Alonso, Mesoraco, Sappelt, Francisco, Cozart, and Frazier will all have graduated beyond prospect status by this time next year. I have included the projected 2012 starting level for each player as well.
1. Yorman Rodriguez OF AA - will follow Adam Dunn and Jay Bruce to become the Reds next great OF prospect
2. Yasmani Grandal C AAA - should earn a quick promotion to Carolina, but may be the most likely candidate to get dealt before next season
3. Billy Hamilton SS A+ - may struggle early in Dayton because of strength questions, but talent is clearly there
4. Ryan LaMarre OF AAA - a runner-up for my breakout candidate of the year, he is also a runner-up for most likely trade candidate due to CF depth
5. Ismael Guillon LHP A+ - if Lotzkar is injured, he is the best pitching prospect in the system
6. 2011 Reds First Rounder ?? - I'm hoping for a big corner bat or a high upside arm
7. Junior Arias 3B A+ - he is a darkhorse that doesn't get as much mention as Hamilton or Torreyes, but could project the best of all of them
8. Ronald Torreyes 2B A/A+ - the Danny Ray Herrera of infielders keeps performing and impressing despite his small stature
9. Drew Cisco RHP A+/AA - the most polished HS pitcher the Reds have drafted in some time could move quickly this year
10. Donnie Joseph LHP MLB - while valuable, I don't consider relievers to be worthy of Top 5 ratings unless they're projected as a clearcut closer, which Joseph is not. Plus I think Joseph should be on the verge of the bigs if not in them by Opening Day 2012
WC: Kyle Lotzkar RHP - if healthy, he could easily vault to the top of the list.
I should mention, I think there is a very good chance at least one of these names has been traded out of the Reds organization by this time next year.
One thing to keep an eye on- if the Reds do draft a power-hitting 1B early in this year's draft, it could be very fun to watch an infield of that person, Torreyes, Hamilton, and Arias move through the system together. Dayton this year, High A next, and so on.