Based off of design, instruction, consistency and politics, this is a realistic placement:
1. Crown
2. BD
3. Cadets
4. SCV
5. Phantom
6. Bluecoats
7. Cavaliers
8. Boston
9. Madison
10. Blue Stars
11. Spirit
12. Crossmen or BK
Not sure where this thought of having a large number of people at audition camps means your corps will move up in placement. Even large vet retention is no promise. Look at Bluecoats 2007, a predominantly vet horn line and the corps fell from 4th to 7th. These days, design is approx. 70% of your success. Members can be solid and instruction at the highest level, but if the design is flawed the overall success of the corps will be limited. The top 6 on the list have consistently proven to design effective shows in recent years. The bottom 6 have not shown enough consistency in design and/or instruction to not have a good year be considered luck. Boston has come close, but still hasn't been able to add up to the corps above. Let's be honest, Boston beat Cavaliers last season because the Cavaliers were not in their prime. Boston had a great show, but if Cavaliers were on point as they have been in recent years, they would not have fallen and Boston would not have moved up. Same goes for Crossmen. Blue Stars were not at their best which made room for Crossmen to shine.
The reality is that the top 12 are eat or be eaten! If a corps slips up, there are several other hungry corps ready to take their place. Or a lower corps may decide to sharpen their teeth, do some things different and best a complacent corps. Regardless, it's exciting and why it's fun making predictions based off of literally no admissible data.