Title says it all. I'm trying to make a list that'll be good against anyone... but with more than half of my games coming from various Space Marine chapters, they will be the emphasis here.

HQ:
Shas'el. PR, FB, TA, HWMT. (97)
Shas'el. PR, FB, TA, HWMT. (97)

Heavy:
Hammerhead. Ion, BC, DP, MT, BSF. (135)

Troop:
9x Fire Warrior (90)
-Devilfish. DP (85)
9x Fire Warrior (90)
-Devilfish. DP (85)
10x Kroot (70)

BSF on the tank is just to eat points, had 6 left over. if I am against someone who doesn't care about me going a point over, I'll take another Kroot.

HQs are for heavy tanks first, then TEQs, then transports, then regular Marines.
Hammerhead clears out transports on the first turn, then Marines from there on out.
FW squads start mounted in the transports, and launch coordinated Rapid Fire routines supported by their tanks. (and I realized that I'd been forgetting to fire with the drones...).
The Kroot will usually Infiltrate into a vaguely threatening position (preferrably in some forest/jungle if I can arrange for it), but they're there mostly to claim objectives and harass opponents, hopefully distracting them from the units that actually matter. Kroot seem to be widely on the kill list of the locals, so they make effective bait.

Many thanks to everyone who has helped me make the list, (yes, even you SM guys who told me your weaknesses for me to try and exploit)