CURRENT VERSONS:
DJOKOVIC: 51/60
Forehand - 8, fairly good but nowhere near the best.
Backhand - 10, joint with Murray as the best on tour.
Serve - 8, nothing majorly special.
Physical Strength & Fitness - 9, he regularly gets tired and exhausted in his matches. Of course, this could just be an act. Knowing Djokovic, it probably is, so he gets a 9.
Mental Strength - 9, nothing wrong with his mentality, but he doesn't like it when crowds are cheering for his opponent

Tactics - 7. He has no tactics. He just grinds. However, he can do far more than Nadal can.
NADAL: 42/60
Forehand - 7, not great.
Backhand - 7, not great.
Serve - 5, he has a horrible serve

Physical Strength & Fitness - 9, is falling.
Mental Strength - 9, same as ever.
Tactics - 5. Nadal has tactics?

He just grinds, like Djokovic.
FEDERER: 44/60
Forehand - 8, still very good.
Backhand - 5, to be honest, it's a joke.
Serve - 7, not as good anymore.
Physical Strength & Fitness - 9, he is old now, but there's nothing wrong with him physically.
Mental Strength - 8, still relatively strong.
Tactics - 7, not as good as they once were.
MURRAY: 52/60
Forehand - 8, very good atm. Far better than what it used to be.
Backhand - 10, joint with Djokovic as the best on tour.
Serve - 8, on and off, though very good when it's on.
Physical Strength & Fitness - 9, one of the fittest guys on tour, though he does get days when he's unsually tired.
Mental Strength - 7, looking better, but it's still not the best.
Tactics - 10, currently the best tactical player on tour. That's how he plays.
PEAK VERSIONS:
DJOKOVIC: 51/60
The same as his current version.
Forehand - 8, fairly good but nowhere near the best.
Backhand - 10, joint with Murray as the best on tour.
Serve - 8, nothing majorly special.
Physical Strength & Fitness - 9, he regularly gets tired and exhausted in his matches. Of course, this could just be an act. Knowing Djokovic, it probably is, so he gets a 9.
Mental Strength - 9, nothing wrong with his mentality, but he doesn't like it when crowds are cheering for his opponent

Tactics - 7 (He has no tactics. He just grinds. However, he can do far more than Nadal can.)
FEDERER: 59/60
Forehand - 10, the best.
Backhand - 10, amazing.
Serve - 10, unbreakable.
Physical Strength & Fitness - 10, one of the fittest and strongest guys ever. Hardly ever got injured.
Mental Strength - 9, not the best, but still very good.
Tactics - 10, unstoppable.
NADAL: 45/60
Forehand - 8, overrated, but still very good.
Backhand - 7, it's never been great.
Serve - 6, has always been mediocre.
Physical Strength & Fitness - 10, one of the best, though his constant timeouts would get him a lower score, if it wasn't for the fact that they're all fake.
Mental Strength - 9, very good usually.
Tactics - 5, he's just a grinder.
MURRAY: 52/60
Forehand - 8, very good atm. Far better than what it used to be.
Backhand - 10, joint with Djokovic as the best on tour.
Serve - 8, on and off, though very good when it's on.
Physical Strength & Fitness - 9, one of the fittest guys on tour, though he does get days when he's unsually tired.
Mental Strength - 7, looking better, but it's still not the best.
Tactics - 10, currently the best tactical player on tour. That's how he plays.
Yes, I know I put Murray above peak Djokovic, but that's based on these categories. Overall, Djokovic is obviously better atm, though Murray is very close and at his peak, would be on a similar, if not higher, level.