What I have to work with

The first thing that I wanted to take a look at was the actual models I owned and what I could do with them.  Thankfully I hadn't gotten very far with my original plan of updating the Crimson Fists (all of which are Rogue Trader Era models) to the recent edition's Space Marine Codex.  That made squad construction easier.

Here's what I have.  Most of the models are completely RT Era.  In some cases, such as the Land Raider, I've had to convert (often times using contemporary model parts) the kit because it was incomplete.

Squads:
1 Tactical Terminator Squad with Assault Cannon.  I have a Heavy Flamer and a Cyclone Missile Launcher that I can swap into this squad if needed.  I have an additional Assault Cannon Terminator, too.

1 Assault Terminator Squad with two Thunder Hammer/Storm Shield Terminators, two Terminators with Storm Bolters and Power Gloves, and a Sergeant with Lightning Claws.  I'm keeping a lookout for RT Era Assault Terminators to fold into this squad.  If I can find a couple, I have a decent chance at building a second Tactical Terminator Squad.

3 Tactical Space Marine Squads.
All three squads have a Sergeant with a Power Glove. One features a Missile Launcher and Flamer, a second has Plasma Gun and Multi-Melta and the third features a Conversion Beamer and a Graviton Gun.

1 Devastator Space Marine Squad.
This squad has a Sergeant armed with a Boltgun, two Heavy Bolters, a Lascannon,  and a Missile Launcher.

Characters and Individual Models:

Original RT Era Assassin (the model looks like the inspiration for both the Callidus and Eversor Assassins).
Inquisitor
Assault Space Marine with an original Jump Pack (which will most likely be a Hero)
A Scout Model that I might paint up as a Rogue Trader.
A Techmarine on foot.
A Techmarine on a Vincent Black Shadow Bike.
3 Librarians
1 Terminator Librarian
1 Terminator Captain with Stormbolter, Power Glove, Power Sword and Grenade Launcher
1 Chaplain
1 Space Marine with Power Fist and Bolter (also very likely to be used as a Hero)
2 Medics
1 Marine with a Bolter
1 Marine with a pistol and a chainsword (one of the aforementioned original Space Marine Models)
1 Marine with a lasgun w/bayoney (another of the original Space Marines.  I'm counting this weapon, which bears no real resemblance to any other lasgun, as a Graviton gun)
1 Space Marine in an early version of Artificer Armor

Vehicles:
1 Furibundus Dreadnought (features two Boltguns on the right arm and a Lascannon on the left arm)
1 Land Raider
2 Whirlwinds (converted from Rhinos, as described originally in White Dwarf)
4 Rhinos, featuring original railings on three of them and all original Bolt Guns.