I find Nole to be more likable than Rafa.
However, Srdjan Djokovic is the major obstacle for me to fully enjoy Nole's games. He is even prouder than Novak himself, which doesn't make sense because those are his son's achievements, not his! He always has a hostile and arrogant air about him (unlike Nole, who is arrogant but friendly), and he cheer at every unforced error of the opponent. He is the Yuri Sharapov on men's tour, only more lamentable because Novak is 100 times more likable than Sharapova.
Toni Nadal is not Robert Federer, but he is a legendary tennis coach (something neither Robert nor Srdjan is), and a plain-speaking philosopher. I'd much, much rather have Toni Nadal in my box.
Quantitatively, in terms of likableness:
Robert Federer = 10
Novak Djokovic = 8
Rafael Nadal = 7
Toni Nadal = 7
Roger Federer = 6
Maria Sharapova = 4
Yuri Sharapov = 2
Srdjan Djokovic = 1
The problem with Federer's box is Robert and Mirka are always with some vapid celebrity that is friends with Roger. I mean Gwen Stefani, really? At least the Djokovic family scares off obnoxious hanger ons.
Though as far as celebrity hanger-ons go, I think the French players have the advantage, as the Thierry Henry cameo was one of the few good things about Mugfils' US Open campaign.