[masterofweirdness]

HQ
1x Master Captain Sicarius (Lightning Claws, Artificier Armour, joined to squad Artox) = 125pts

Not bad... but, I think this guy could do without Artificier armor. Its just not worth the points when most units that attack this guy will have power weapons or better. I'd go with an Inv. Save... combat shields are cheap, but Iron Halo's give a much better inv. save, even if it is expensive.

Elite
5x Assault Terminator Squad Troika = 200pts

Add another model... what weapons does the squad have? I would say getting 1 or 2 thunder hammers and the rest have lighting claws. You get much better. Inv. Save AND the ability to smashy tanks and the like.

Troops
8x Space Marine Squad Artox (1x Heavy Bolter, 1x Melta Gun, Rhino, Vet. Sgt with Power Fist, Rhino) = 215pts

I don't like this squad.... first off, drop the Heavy bolter. Second, replace it with frag grenades. A Heavy bolter, while nice and cheap, doesn't really fit in a Rhino Squad. Also, consider getting 2 more marines... most likely from your other squad.

10x Space Marine Squad Kharne (1x Missile Launcher, 1x Plasma Gun) = 170pts

This squad is fine.

5x Scout Squad Scaro (Armed with BP & CCW) = 65pts

Add at least another model... consider filling it up to 10 men, adding a vet. sarge w/ powerfist, and frag grenades.

Fast Attack
10x Assault Marine Squad Beltharius (1x Plasma Pistol) = 225pts

This squad is okay... but like Stitch said, I think it should be dropped totally, that or 6men + flamer.

Total
1000pts - 40 models

Actually, this army isn't bad... even if I did rip it to shreds...