There is no way to explain the imbalance of the system with analyzing every aspect of the race. It is much more simple and logical to compare the units that serve similar functions to determine if the races are truly balanced or not. I felt like I had to write this because I believe Terran is an imba race.
Starcraft Progamer Scene : Terrans have been dominating the Starcraft Pro gaming scene for a very long time now. From the rise of famous Boxer, oov, Nada, Flash, there have always been solid Terran champions. Even the Terrans who don’t make it to the top have always looked strong: Xellos, Hwasin, Iris, Midas. The sheer fact that there are more successful Terran dominant players support the argument that Terran race is much easier to master because it has always been advantageously overpowered.
So why would I think that Terran is an overpowered race? Well, two words simplify everything: Cost Efficiency. The game of starcraft is all about getting enough minerals and resources to build an army to destroy the opponent. The more money = bigger army. If your units are cheap and powerful, then you can build lots of them and have a much bigger army to stomp your opponents.
Vulture:
75 Minerals, Comes with 3 useful mines. Very Fast. Mines cost nothing to use, and can even serve as scouting tools. Vulture is very flexible unit, meaning they can be easily microed. They kill probes/drones in 2 shots while Dragoon needs 6 whooping hits to kill an SCV. Very ideal for harassing the mineral line, scouting units, and front line meatshields because they are so cheap.
Solution: The cost of Vulture must be raised to at least 125 minerals. Give just 1 mine per vulture OR put 1 supply cost for each spider mine planted.
Tank:
150 Minerals 100 Gas 2 Supply, Longest Range, Very High damage and splash damage. Does something sound wrong here? How does something that does 70 damage with huge range only cost 2 supply? This is the reason why many players say 200/200 Terran army will beat a 200/200 Protoss army straight up. Because Tanks cost the same supply as a freaking Vulture or Dragoon. How is that not imbalanced?
Solution: Make Tanks cost 3 Supply
SCV:
50 Minerals, 60 Life. Drones and Probes have 40 life total, but Terran SCV has 60…why? Because Drone and Probes have regenerating life? Yes, that is true, but regeneration takes very long time which makes it useless. Terran might not have that, but they have something better called repair. Its much faster and efficient. So what is the point of making Terran SCV 60 Life? Dragoons already need more than 2 hits to kill an SCV compared to Vulture’s type of damage that allows it to 2 hit probes/drones. Why increase the life of SCV to make it take 6 hits instead of 4 hits for Dragoon to kill it?
Solution: Make Terran SCV 40 Life
Marine/Medic/Firebat: These units are so cost efficient that Terrans can make a huge group of them in time without an expo. This is the reason why Terran > Zerg in TvZ. If Zerg loses his Lurkerling/ Mutaling army, Zerg is pretty much screwed. Same for Terrans? Nah. By the time they die, another huge group of m&m is already built and ready-to-go. Very cheap cost that almost makes the game unfair. 6 Firebat in early game can make 30 Zerglings take huge casualties…all at the cost of…300 minerals and 150 gas?? But 30 lings cost 750 minerals…
Solution: Marines cost 75 minerals, Medic costs 75 minerals 25 gas, Firebat costs 75 minerals 50 gas. Stim is automatically available without researching.
Turrets: 20 Damage, Attack Air only, 75 Minerals
Very cost efficient, compared to cannons and spore colonies. Spore does 15 damage, and costs 175 minerals (including drone) That’s more than twice the cost of Turret but does less attack damage than it. Yes, spores have more life than turrets but turrets are repairable.
Cannon seems like a fair-deal because it costs double of Turrets at the reward of being able to attack ground as well but this is actually a bad thing. When Units from dropships get pounded by cannons, as soon as units start dropping, the cannon starts focusing on attacking the units dropped instead. That means that the dropship is safe and so are the other units in the dropship. Not to mention that turrets shoot faster than cannons as well.
One other thing cheap about turrets is that they can be build anywhere on the map unlike cannons or sunken/spores. Cannons need pylon and colonies need creep. Turrets can serve as anti dropship during large battles, while Protoss cannot do the same (pylon/cannon take too long to build, time-wise and cost-wise)
Solution: Make Turrets cost 100 minerals, make Turrets do 15 damage.
Goliaths: Oh boy. The most promising ground to air unit has arrived. Initially it does 20 damage but with full upgrades, it can do 32 damage to air units per attack! Furthermore, they have long range, cheap 125 minerals 75 gas, and does decent damage to ground units as well.
Solution: Goliath cost should be turned up to 125 minerals and 125 gas.
Terran Dropship: Not much problems here, except the fact that they are faster in speed than an unupgraded shuttle. Need to be the same speed as un upgraded Protoss shuttle to make things fair.
Concepts:
Terran Metal Upgrades: Very Unproportional. I can understand Zerg upgrades only giving +1 attack because Zerg uses large quantity of units, and Protoss units getting +2 attack per upgrade because P units are expensive and few, but why does Terran metal units get massive unbalanced digits of upgrade? For example, Siege Tank does 70 Damage without upgrade. Each upgrade will give it 5 damage, so a fully +3 attack Siege Tank will do 85 Damage! That’s 15 more damage for 3 upgrades!
Solution: Tanks/Goliaths/Vulture only receive 2 attack more per upgrade.
Terrans should not be allowed to wall-in. This allows for smaller Terran army to be safe from a larger Zerg / Protoss army. On the other hand, if the T army is bigger than Zerg/Protoss army, then they have to quickly build more units or they will get rolled over.
Terrans should not be allowed to lift off. How is it that a less technologically advanced race (Terran) can lift off while a more advanced technology (Protoss) cannot lift off? Lift off allows Terran to be safe from pure-ground army. This is very useful because in TvZ, Zerg will naturally not have any hydras, and just enough scourges to destroy dropships/vessels. So when a Zerg overruns a Terran expo, the Terran CC is safe from simply liftoff. Zerg hatchery cannot be safe from a Terran attack.
Furthermore, Terran players abuse this concept farther by planting hidden mines under the lifted off building. Naturally, most players will not know about this.
Solution: Allow Zerg buildings to “burrow” or Prevent Terran buildings from liftoff. Another solution might be: Terrans need to research liftoff at CC. When lifting off, there is a 10 second delay before preparing to lift off.
Maphack Scouting: Zerg uses suicidal lings or suicidal overlords to gather scouting information. Protoss has observers which can initially seem safe because of the cloak, but Turrets will render that useless. Observers cannot go where there are turrets, meaning it will be blocked away from at least half of the Terran base.
Terran has Science Vessel to detect and scan. But they also have comsat. This allows them to see anywhere in the map at the cost of energy. 50 energy might seem fair but at the age of fast expanding where you will see 2~4 command centers per game, that 50 energy cost is more like 13~25 energy. It is pretty much the most reliable and safe sort of scouting in the game.
Solution: Raise the cost of comsat station. Lower the area of degree of vision from scan by 50%.
Terran Tech Tree: A huge problem in Terran tech is that everything is very easy and relatively fast to get to. Zerg needs to upgrade to lair then to hive to reach the later tech (ultra, defiler) while Protoss needs to build a series of building requirements to reach arbiter tech (cybercore -> stargate/templar -> arbiter)
This might not seem like a big deal, but it actually is. It allows for Terrans to reach their late techs relatively easier than other races, allowing Terran to drop much faster than Protoss/Zerg ever could, allowing Terran access to irradiate (Terran high-end tech) when Zerg has mutalisks (mid-game tech units)