Uhhhg hate to even put this out there but perhaps some weird Ad Mech contingent on the expedition?
Then you have plenty of freedom to go and make anything weird you want to fit into that slot =/

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It's a thought. Could dress it up as Ad Mech/Squats/random aliens. Make it 0-1 or so and all is well.

_________________
The Apocrypha of Skaros 1.1
Rogue Trader Expedition 0.4
The Horus Heresy 0.5
Night Lords 0.1
My Trade Thread

OK. Having pondered for a bit, I think two units might do the job.

Bondsman Aerospace Fighter
Bomber 4+ Sv
Turbolaser (30cm - AP5+/AT3+/AA5+, FxF)
Melta Warhead (15cm - TK(1), FxF, OS)

Basically a space-borne fighter pressed into service in-atmosphere, where it ends up serving as a bomber. I was pricing at 275, though I think I may be overcompensating there.

And:
Thunderhawk (Zero-Gravity Bombing)
Bomber, 4+ RA Sv
Usual sets of Heavy Bolters
Turbolaser (45 cm - 2xAP5+/AT3+/AA5+, FxF)
Plasma Warheads (15cm - 2BP, MW)
Melta Warheads (15cm - TK (D3), FxF, OS)

Pricing at about 300. Which is probably high, but possibly not.

Thoughts? The list would then be a somewhat eclectic bunch of infantry with some heavy duty aerospace support.

_________________
The Apocrypha of Skaros 1.1
Rogue Trader Expedition 0.4
The Horus Heresy 0.5
Night Lords 0.1
My Trade Thread

I'd swap it for the Starhawk Heavy bomber. It's basically that loadout you list there and more generic Imperial as opposed to something Marine traditionally.

_________________
He's a lawyer and a super-villian. That's like having a shark with a bazooka!

-I HAVE NO POINT
-Penal Legion-Fan list
-Help me make Whitescars not suck!

I was thinking of the Starhawk (or whatever the fighter is), but didn't know where to find stats. Where should I be looking?

EDIT: Ah! Found some.

However, the Starhawk appears to be massive. As in, twice the size of a THunderhawk and three times the size of the Marauder massive. And that's at a minimum - it could be even bigger.

Could just do a space variant of the Marauder - they're the Imperial Navy's second-line space bomber, so it'd make sense for Rogue Traders to be using them. And there's already a model, as an added bonus.

I shall ponder stats for a little bit.

_________________
The Apocrypha of Skaros 1.1
Rogue Trader Expedition 0.4
The Horus Heresy 0.5
Night Lords 0.1
My Trade Thread

OK. There's a couple of options for what to do with the Plasma Bombs that a Marauder Starbomber (better name suggestions very, very welcome ) would mount.

Option 1: 2BP, MW. Doesn't seem like it could really handle starship armor, though. Squadron of two, so in practice it'd probably end up being used on large infantry formations as much as on Titans or the like. Not sure that's what I want.

Option 2: MW3+, TK(D3). Nastier, but they ARE anti-starship bombs. And they'll definitely be used on War Engines instead of on infantry or armor. Squadron of one or two - not sure.

Option 3: 1 or 2BP, MW OR MW3+, TK(D3). Should be priced accordingly, since that's definitely the powerful option. Squadron of one (with 2BP) or two (with 1BP).

_________________
The Apocrypha of Skaros 1.1
Rogue Trader Expedition 0.4
The Horus Heresy 0.5
Night Lords 0.1
My Trade Thread

I work on an RT-Party too. In my list the RT had more the feeling of,only Ground-Attack when needed, so they are a more Speedy Army. So the Standard Ar Kinsmen in Rhinos. The War-Machine Problem i fixed with an 0-1 choice of an Artifact-Heavy Tank or an Squadron Choice, like Executioner Squad or Fellblade and so one. And too characterizing You have the choice of the Kind of Tradestyle. 2-3 choices. So you have Deatachment of AM, SM, IG, Criminals with Xenos and Mutants and Renegade with Chaos. I think on Inquisition and Genestealer as Choices.

Ps. My Spacebomber Called Starscream.