If it were my choice i'd take Senna and drop Rubens and keep Sutil.
Interesting James, that you see Sutil as being a better prospect than Rubens ? Sutil wasn't a very good development driver nor was he an outstanding racer. Rubens is a proven race winner, albeit in superior machinery, and is a great development driver. He has been portrayed as "old school" and is certainly limited as far as age is concerned. But Sutil has peaked, according to those who know. Where's the potential ? Steady or proven ?
Really though Sutil, who is average at best, over Barrichello ?