Well, I've always been a fan of Protoss, they are my fav. However, a good Zerg player is really devastating. My friend plays Zerg and he always does massive damage with them lol. I'd say Terran is the weakest. They don't have many strengths compared to the other races. Also, depends on what type of maps you play. If you play Zero Clutter / Fastest possible maps, then Zerg is probably an even better choice. However, on regular maps, things are a little more even. At least thats my opinion anyway lol.