mrz, while you are right that #1 is totally wrong and bound to lose, cheese tactics are actually viable at the pro level (although for Terran the preferred ones are reaper harass and fast Banshee, or occasionally fast Hellion vs Zerg if they fast expand).
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Terran vs Terran is all about Vikings or Banshees (usually one person rushes Banshees and the other reacts by rushing Vikings), with the Viking player often using tanks while the Banshee player is usually more focused on MMM (see below).
Terran vs Zerg is mostly MMM but fast Hellion and fast Banshee can also be deadly. Also, Thors are good in this matchup (get one or two, they destroy Mutalisks, Hydralisks, and Roaches, and soak up damage really well if you have four or so SCVs with them to repair). Also remember to put missile turrets in your mineral lines since Mutalisk harass is the name of the game. If they fast expand, you either want to rush them or fast expand in response. You also might want one or two Siege Tanks since Spine Crawlers really hurt. You also might want one or two Ghosts to EMP their Infestors since Infestors really hurt. Combat Shields are really important here since your Marines will usually be doing the tanking.
Terran vs Protoss is basically MMM again, but Banshees are very strong in this matchup, and Tanks can be sometimes. Marauder rushing with Concussive Shells is deadly, and Stim Packs are key. Void Ray harass is painful, but stimmed Marines are great at countering them. Missile Turrets and Vikings are terrible against Void Rays, so stick with Marines, and they'll be forced off air soon since it isn't cost effective.
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MMM: Marines, Marauders, Medivacs. You will want around 5 Barracks for a fully saturated base, and around 7 or 8 for two. About 1/2 Tech Lab, 1/4 Reactor, 1/4 empty should be good. Put a tech lab on your first Barracks and get Concussive Shells as soon as possible in every matchup except TvT or in very specific builds: Concussive Shells allow Marauders to kite Zealots, Zerglings, Roaches, and even Speedlings, and in general make life hell for Protoss and Zerg. Try to get stim soon after, and go about 5/8 marines 3/8 marauders with one reactor'd starport keeping your medivac count around 6 or so.
I'll post some replays of me (platinum 1v1, but some of the older ones are gold) in a day or so.