Haha, this is the third time I've posted something about this topic, but I don't mind, I always love adding my two cents, haha :]
Play whichever race you have the most fun with, is my own personal opinion. If you are playing the race you have the most fun with, then learning how to overcome your problems and improve should not be a problem and be part of the overall fun you're having while playing P/T/Z.
Don't worry yourself with which icon is sitting next to your name or how many points you've obtained/lost... focus on improving as a player and the promotions, ladder points and tournament wins will all flow accordingly. Because at the end of the day, in SCII; losing = improving = winning = promotion.
But yeah, to wind up yet another ramble of mine; play whichever race you have the most fun with and learn how to excel using that race. GL&HF with whichever decision you make :]
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