I bought starter and all factions for v1, read the rules, played probably 10 games, never learned what should be in a strike team except Rule of Cool. Got my hands on books for v2, , read the rules, got two more factions, played probably 10 games, still dont know what should be in a strike team.
For instance, last time I played with marauders, had ton of armour piercing weapons and all was useless as my opponent played with Veermyn who had no armour.
So, I am thinking that good team should have mix of melee and ranged units from grunts, one long range support unit like sniper, one tank unit to soak damage from fragile units. one specialist unit do dish damage.
But Ilike I said, still dont know what is good build for any strike team, so If I manage to get another game, my 200pts Plague will have stage 1 as commander, Aberration, 3 Leapers and 12 zombies