Dawn of War

Tau
Opening: BB                                         <- quickly! [Cadre HQ] SSSS [Rally] Ctrl+0 [Tau Barracks] FF (auto-queue Commander)   <- quickly! . BP BL, BL, BE

Necrons
Opening: [Capture] RR [Monolith] SSSNNL Ctrl+0 4 x BP (6 in all)

Space Marines
Opening: BC 3xscouts, 1xservitor MMMS 2xSpace Marines 2xPlasma Notes:
 * Infiltrated scout marines with infiltrated skull probe and sniper rifles should be very annoying.
 * Heavy bolters seem better than plasma.
 * The orbital relay can be loaded with fully upgraded squads, which can then be dropped into battle.
 * The Rhino is fast, cheap to build, doesn't take up vehicle cap, so if it's affordable, there's no reason not to build it. Marines can fire heavy weapons immediately when exiting the Rhino.
 * The Chaplain has a healing aura which regenerates units close to him. He should be attached to a squad of Grey Knights.
 * Librarian Smite deals insane amounts of damage and can kill entire squads.
 * Don't use Hellfire Dreadnoughts.