Federer and Djokovic are 9/9 in finals reached, Nadal is 8/9.
Different titles won: Federer, Agassi, Djokovic 7/9
Federer is missing Monte Carlo (reached 3 consecutive finals - lost all 3 to...wait for it...Nadal, reached 2 Rome finals - 1 lost to Mantilla, 1 lost to Nadal)
Djokovic is missing Monte Carlo (2 finals lost to Nadal I think) and Cincinnati (4 finals lost...2 to Federer and 2 to Murray I think).
I don't think Federer has it in him to win Monte Carlo and Rome even without Nadal in the draw, he's not even playing MC btw.
I could see Djokovic winning Monte Carlo if Nadal is not in the draw or he's not in good shape (I assume 2013 is his best chance). In Cinainnati Djokovic has just been plain unlucky, reached the final on 4 out of the last 5 editions and twice lost to Murray/Federer. He should win it at least once in the future.