What's kinda weird to me, but interesting, is that Space Marines are supposed to be simultaneously shock troops (thus the color of their armor), guerilla forces, and indomitable defense forces. I mean, yeah, it probably depends a lot on the chapter and company we're talking about, and they're all-around elite badasses, compared to everyone else, but it still seems funny.
Question for more veteran lore-nerds. Considering the main 1000 marines are just the companies infantry units, not considering the detachments allowed to the various strike cruisers and battle barges for boarding defense/command, or the vehicle drivers and various additional techmarines assigned to the ships and vehicles, how many marines do you think would make up a typical, mostly-Codex compliant chapter of the Adeptus Astartes? And how many of those do you think would be techmarines?
Also also, I don't know too much about the geneseed, but while I'm fairly certain the Primarchs are all basically half-magic in the first place, would a race like the Tau, Dark Eldar, or maybe the Eldar(the tech-savvy races, basically) be able to sequence the genes if they got a fully grown Space Marine corpse or ten? They might not be able to recreate them very easily, but would it be technically possible, or is there a part of the geneseed I don't know about, or would the typical Chaos shenanigans on anything to do with gene manipulation occur(well obviously they would but is it a necessity or just GW?), and so on.