There is no best pro to emulate.
However you can look to ones that have the same body type and stature you do and play style. Players have made the best use of the same gifts so I would nudge you toward toward one of those players.
A lot of people say Fed but he's unique in his body type (really broad shoulders and long arms) and has extreme flexibility. Just because he's the GOAT doesn't mean he's the right model for you.
For example, it you are like 5`8 like myself. Look toward some of the shorter players. These players might not be even house hold names but they will help you alot (i.e.Tipsy).
I watch some people play at futures that weren't even 6 foot but wow could the cover the court and accelerate the ball.
And I have to emphasize you have to find someone who's game relates to you. If you're a baseliner you're not going to find much help emulating Llodra. If your a finesse player watching Nadal or Tsonga isn't going to help you much. etc etc.
I hope this helped.