Welcome to the Ultramarines 3rd Company! Which, as is known, is the best company of Ultramarines.
I field mine like this:
If you want to keep it purely as a company force, you need to ditch the pred. That’s a chapter level asset. Also, the dread is an elite pick.
I think your best starting point is going to be a battle demi-company. Especially if you want to keep it pure 3rd co. You are already restricting yourself, might as well get the free bonuses. I find that 3 full
tac squads, 5 men assault and
devs, plus a
HQ makes for a tidy 1,000 point list. Add the dread and you should be at your 1,200 level.
Onto specific commentary on your list:
Where is the captain going? What’s his job? I don’t see a place for him in your list. I’m going to assume you have the mono-pose captain, and that’s why his gear is what it is. But it’s not a particularly good loadout. If you do want to field him, call his sword a relic blade. He should also probably be in a drop pod with a command squad if you are going to field him on foot. If you are looking into the future, jump packs fit well in company lists.
SM HQs want to be in
CC, and the assault squads are your boys for that.
I’d not mix
MM in a
plas squad. Either go full melta, or swap out the
MM for a
HB or
GC, depending on points. Probably grav is this is going to be a monster hunter squad.
HB/F c-flamer is a good squad for cashing out gribbles..
I only hand out melta bombs to even out points. Nice to have, but points can often be spent better elsewhere.
The only reason to give the Evis to the sarge is if you make him a vet. If not, you are better off just hiding it in the squad, so he can’t be challenged out. Especially if there isn’t a
HQ there to accept. No reason to have both the Evis and the
MB on the same guy either.
I’d not bother with the melta on the
Dev sarge. I experimented with a c-grav on a
dev squad for a bit, but their habit of hanging out in the backfield meant I never had anything get in range to shoot. The c-melta is going to be even worse for that. Just keep him bare-bones.
MLs are generically OK. Should do reasonably well vs. nids. While I’m normally loath to recommend them, you might want to think about flack missiles. One of the worst
AA options available to us, but they do fit in the company, and there are flyrants out there. Giving them a transport when they have long range weapons is purely a fluff thing. But they are better off just hunkering down in cover, not hiding in a box.
If you are going with a
MM dread, you probably want a pod for him. If not I might suggest something a bit better for walking across the table. Probably worth upgrading to a
HF to burn out the hordes.