First off, the book is fantastic. BoLS has a quick overview, but I'm really impressed by the physical book. It is huge, beautiful and well put together. I feel like I got my money's worth in mass, if nothing else. While waiting for the book to arrive, I re-read the first few Heresy novels and decided I wanted to do a Isstvan III Loyalist army, centering around a core of two big Sons of Horus/Luna Wolves tac squads. Here's what I came up with for a first go, using the Sons of Horus list:
HQ
Garviel Loken
Siege Breaker, Nuncio-vox (unlocks Phosphex Shells for the Medusa)
Librarian, Mastery Level 3, Refractor Field, Artificer Armor
Elite
Contemptor Dreadnought Talon (2): Kheres Assault Cannon, Graviton Gun
Legion Destroyer Squad (5): PF/Artificer Sarge, Missile Launcher with Rad Missiles
Apothecarion Detachment (1): Augury scanner
Troops
Legion Tactical Squad (20): Nuncio-vox, Legion Vexilla
Legion Tactical Squad (15): extra CCW, PF/Artificer Sarge
Heavy
Legion Heavy Support Squad (5): 4 Lascannons, Nuncio-vox/Chainsword Sarge
Legion Medusa, Phosphex Shells
2000 points
Thursday I played a Heresy game against Bigred's Death Guard army. He made up his list on the spot from his gigantic collection and it was similar to mine: two big Tac squads, two Heavy Support squads (Multi-meltas and Lascannons), a squad of two wound Terminators.
It turns out the 5-man Destroyer squad is pretty soft, especially when shot at by 20 dudes with Bolters or seven Lascannons. I liked the Phosphex Shells, but I think I'd prefer to have a character that is a little more killy and I think the S10 Medusa might be better. I ran the Librarian with Pyromancy, but ended up with Fiery Form, Inferno and Spontaneous Combustion (too many Shooting powers). I think next time I'll try Biomancy and try to get Endurance, which would make for some fun. Anyway, here's the next revision:
HQ
Garviel Loken
Legion Champion, Master Crafted Power Weapon, Combat Shield, Artificer Armor
Librarian, Mastery Level 3, Refractor Field, Artificer Armor
Elite
Contemptor Dreadnought Talon (2): Kheres Assault Cannon, Graviton Gun
Apothecarion Detachment (2)
Troops
Legion Tactical Squad (20): extra CCW, PF/Artificer Sarge, Legion Vexilla
Legion Tactical Squad (15): Nuncio-vox
Heavy
Legion Heavy Support Squad (5): 5 Missile Launchers
Legion Medusa (2)
Fortification
Aegis Defense Line
2000 points
Legion Tactical Squad (20): extra CCW, PF/Artificer Sarge, Legion Vexilla
Legion Tactical Squad (15): Nuncio-vox
Heavy
Legion Heavy Support Squad (5): 5 Missile Launchers
Legion Medusa (2)
Fortification
Aegis Defense Line
2000 points
Bigred is a big proponent of the Aegis, but I'm not too sure a 3+ squad of 15 with an Apothecary makes it worth-while. I do want a more mobile element, and if I could guarantee Gate of Infinity I'd go for that. The next thing to add with be something that provides some mobility, maybe a Dreadclaw for one of the Contemptors and a Justaerin squad to drop in, too.
I think the Legion lists don't really come into their own until 2500 points. If you are playing with a Primarch I think 3000 might be a good number. Of course, I'm sure this is no accident on Forgeworld's part.
More, including some painting, coming soon.