Here are my thoughts and opinions on the 3 races. Terran easily the best race in sc2 but also the toughest to master. almost every unit has some sort of special ability that can either be upgraded or already comes with the unit. In the hands of a professional player look for Terran to become the number 1 race used by pros world wide. Zerg is a race more suited to back up roles early on in multiplayer games that are 2v2's or more. the roach is their best early ground unit but with a couple marauders or a quick immortal the zerg will be in tough until teir 2.5-3. I mind you, getting to teir 2 or higher might be simple enough u may say but with a high price tag on gas and minerals, producing enough units to effectively combat your opponents forces may be a challenging task. Protoss Possibly the most balanced race in the game with a good variety of ground units and air. Look for the Protoss to be a solid choice is most matches. Protoss posses a strong ground game with a moderate air force the Protoss main weakness is in unit production and a slower economy that needs a lot of attention with the chrono boost ability found at the nexus I also believe the Protoss big glaring weakness and i guess can be said for the Zerg aswell is the inability to handle MMM without a lot of micro management or Templars Psi Storm . Also be wise when using chrono boost because you might need a chrono boost to help build a zealot or stalker at your gateway because of incoming attack but only to find you have spent all your energy on chrono boosting your nexus for faster probes to boost your economy
I agree with most of what you say but Zerg: Their units may be simple and get crushed in head on fights with balanced armies but they have two clear advantages. They can instantly change direction in unit make up if they see an unbalanced enemy force (via larva) and creep, overlords and cracklings mean harrassment is the name of the game. Zerg is suited for creative hands. Tier 2.5-3 is for when you have the enemy controlled and need a way to break them.
I'd say Zerg just needs a buff and then the game would be pretty balanced. The only thing Zerg has going for them right now is the fact that they can get a bunch of Infestors, burrow them, and rain Infested Terran on the mineral line. Although I think a lot of it might not be balance issues and could just be the fact that people don't know how to correctly play with certain races yet. A lot of the units and abilities are different in SC2 than they were in SC1, so it's very likely that people are still learning how to play certain races and how to counter certain strategies.
re IMO the main glaring weakness of the Zerg is they dont have a heavy air to air unit. Terran has the Battle cruiser and the Viking. Protoss have Carrier, Phoenix, Voidrays, and Mothership. The Zerg have..........they have..........well they have..............um.............well what do they have? Sure you can produce 24 Muta's at the cost of several of those other ships but if you have 24 Muta's and here come 6 or 7 BC's or 12 Vikings or Phoenix's with Voidrays you are screwed. At least they have a heavy ground unit the Ultralisk. But from the dozens of video's I've watched it's rarely used and when it is it's mainly to soak up damage while smaller units attack.
Broodlords. Heavy damage from long distance, not the same thing as BC's, Carriers, or MoShi's, but that's the point of SC. Don't count out the abilities on the Overseer either. People just need to figure out how to build those. The fact that they have huge map awareness from the get go with ovies shouldn't be ignored either. Or they should just make the overmind a buildable unit/building that literary slides around the map ROFL stomping everything. EDIT: While "Zerg Free Radio" plays.
Bloodlust. It could be cast by the overseer/corruptor/queen with a small area of effect like psistorm. Units in that area at time of casting become buffed with 30% increased attack speed. Lasts maybe 15 seconds. Costs maybe 75 energy.
I believe a good unit to balance out the zerg would be to bring back the Lurker or at least a similar type unit as the lurker.The effectiveness of the Lurker for both defense and offence is must when combating large number of marauders/tanks or stalkers and zealots. plain zerglings and roaches are just not enough
I agree, Terran is pretty fierce right now. I think they need to reverse the Sentry nerf that they introduced a few patches ago. Throwing a couple sentries in the mix really helped versus the Rine/Rauder attack, but now with the nerf it's tough to justify making too many of them. I don't know that I would say Zerg is weak--they're just different. You have to play harass. The ling speed is deadly vs toss, the early roach rush has to be accounted for, and the ability to switch army composition on the fly makes predicting their next move next to impossible. I'm sticking to toss for now. I haven't seen anything unstoppable yet, but my Terran ally tells me that the Rine/Rauder push vs toss in 1v1 is money.