How do?
A belated spin off to another thread up in General Discussion, where the topic of restricted choice came up in relation to games of Horus Heresy.
In short, one opinion was that choice was more limited than 40k, as players have a choice of but 18 Legionnes Astartes to choose from in terms of the flavour of the force, and less at present due to some not yet being covered by the (excellent, if pricey) Forgeworld Volumes.
But I for one would like to challenge this perception, and argue the case that there is just as much choice in Horus Heresy as there is 40k, albeit as long as you don't mind playing Marines for the most part.
You see, Legions do not equal Chapters as we know them in 40k. Indeed the Legionnes Astartes fought in a manner more familiar to Imperial Guard players. Massed infantry (basic Tactical Squads go up to 20 Marines, which can fire twice in a turn if you wish), plenty of Tanks (squadrons of 'em, and more choice), artillery trains, entirely airborne assaults etc.
I'll take it as read that you're aware of where a Legions predelictions come from, and that each Legion offered a particular specialisation, a certain theatre of war where they truly excelled. And with this, it's really easy to lose site of the fact a Legion could fight in any theatre of war. White Scars were equipped for siege warfare, albeit to a lesser extent than Iron Warrior or Imperial Fists. Space Wolves were equipped for covert missions, it's just the Ravenguard and Alpha Legion are more famed in that regard. So and so forth.
In short - a Legions specialisation was by no means a limitation. Every officer and every Primarch could take on any challenge without needing to request support from a brother legion perhaps more suited.
But how was this done?
Pretty simple really. Chapters.
Yes folks, Chapters. Not in fact an invention of The Codex Astartes laid down by Guilliman after the fact, but a long standing level of organisation within the Legion.
In most Legions, a Chapter was as it is today. Roughly 1,000 battle brothers with their requisite support from the armoury and command staff. Main difference was certain Chapters represented specialist formations - and this is where you would find say, White Scars siege specialists and that.
So with that in mind, your Legion is largely just a matter of selecting a colour scheme should you wish it. You may not necessarily make the most of any legion perks, but none of them are particularly game breaking.
And those colour schemes? Totes not as set as you might think. There are indeed Legion colours, but we've already seen via the Imperial Fists those were open to variety. And, there's even mention of Astartes using Camouflage when required, opening it up even wider.
But I'm waffling. What's your take on this? Should Legion forces be representative of their preferred methods? Do you already have a Chapter all your own? (show it off if so!)