Can players now be #1's in the past?

The golden age of tennis has brought us athletes that arguably would have been #1s in other eras. Any top 10 player could have been the best player in the world 15 to 20 years ago. Why is this? Is this too bold to state? Take your #10 player, Nicolas Almagro from Spain. What is his weak side? Is he lacking power, maybe speed, or tactical skills? No! He has two strong wings with a good (not marvelous) serve and plays a solid counterpunching style of tennis. But isn't this the age of the offensive player? Yes and No! One can make the argument that it is the age of the transitional player. What made Federer so good, or later Rafa, and now Djoko? The transition from defense to offense. These three do it better than anyone but are followed by Murray and Ferrer who are outstanding counterpunchers. Just like Almagro it is almost unfair to call these players conterpunchers and that's all. It almost gives them a disservice. The players now like Almagro and the other top 9 have no real weak side. They are strong in all aspects of the game. Let's go back to one of the greatest players of all times, Pete Sampras. Arguably the best serve of all times (2nd serve for sure) and a powerful forehand; not to mention great volleyer! So many great strokes but yet there was one missing, the backhand. It's been overanalyzed and discussed on how Pete's backhand was changed from a 2 to a 1 as a teenager. Also, it has been discussed now good he would have been with that two hander giving credence to the argument that his one was just an average shot. Hard to think that one of the best players in history has a "weak" side but it's true. Players now are so much more complete in their skills that if we had a time machine and brought them back to the past, they could have competed at the top of the game without question. Janko Tipsarevic world #9, is strong on all accounts and for a smaller guy carries quite a bit of pop on the serve. So what part of his game would not carry over to the players of the past? It's extremely hard to say. Going up the rankings it the players skills just become more potent making the argument more credible. Take a look at your number one players from the past, Rafter (decent baseline game), Kafelnikov (average serve), Rios (average serve), Muster (too defensive), and going back in the past the players become more and more one dimensional. Let's leave this idea open. Let me know what you think as this has been left very open for discussion.