So the boys and I have geekends of beer, pizza and 40k; that being said, we tend to use aggressively competitive lists. Meta is mostly elite Marine based armies, with one Guard player and an Ork newbie.

After several playtests that affirmed that simply dislocating my 7th ed lists into 8th does not work (assault now being a grievous second to shooting), I've drawn up the following battalion list (or whichever gives 9CP):

Legion: Alpha

HQ: Demon Prince with Wings, MoS, Intoxicating Elixir, Warp Bolter, +1 attack warlord thing (plus Alpharius) - utter beast in combat
HQ: Lord, no extra costs
HQ: Lord, no extra costs

Troops: 2 x 10 cultists with autoguns
Troops: 4x 5 CSM with boltguns

Elites: 3 x Helbrutes with fists and ML

Fast Attack: 3 x 3 bikers with plasma and combiplasma

Heavy support: 3 x 5 Havocs with 3 lascanons

And that's it. It's designed to be simple (everything armed with same options so I don't forget who has what (every single model was converted for the last edition, so I'm f**k going WYSIWYG), bring decent range to make the most of the whole -1 to hit thing. By the time I get close enough that that's a problem, I should be able to combine the efforts of the bikes and brutes to assault key targets with their speed, the Prince is either backing them up for the rerolls or on a rampage elsewhere, and the token gesture Lords are making the Havocs reroll halfl their misses.