The Chaos Space Marine profile in the core rulebook lists "Killing Strike" as one of their talents - with no way to use it since elites don't get fate points. Yet, simply giving each CSM a fate point (or more) seems a bit over the top. And there is also the issue that astartes bolt weapons won't do much to threaten high level Deathwatch killteams. A maximum non-righteous fury damage of 21 (max roll of 10 + 9 + 2 from mighty shot) with penetration 4 will do nothing to a level high techmarine and very little to well equipped members of other specialties. It also makes the volatile quality on plasma weapons pointless.
So I propose a two-fold solution.
1. Each renegade marine gets Touched By The Fates (0). This means they can righteous fury and be a significant threat to killteams of all levels.
2. Each distinct squad-equivalent group of renegade marines has a pool of fate points. Say around half as many as there are marines. Or three. Regardless of the exact number, the GM can use a fate point from the pool as if it was the marine's own.
A squad of eight traitor marines ambush a killteam. They have a pool of four fate points. Halfway through the battle, a marine is in close combat with a killteam member and uses killing strike. Another marine uses a fate point to raise their wounds to survive another attack.
Any thoughts or critiques?