User blog comment:RemosPendragon/Chapter size/@comment-1436455-20150202013517/@comment-8395098-20150202023524

...next to admech and IG they already are a over-hyped self important resource drain. seeing as how many simply backstab the imperium, or decide to do nothing. They have their moments of pure greatness but when you're giving a full cruiser over to 20 pride driven muscle heads who are the only combat troops on the ship...seems a little excessive. The Legio Cybernetica has less ability to betray the imperium and doesn't waste space ships to transport 20 soldiers. the Legio Titanica...well Titans are Titans. The IG is sardenes in a can when they get on most space ships. and none of these organizations are given the rediculus freedoms Space Marines abuse.

but no size in terms of just the chapter doesn't matter to some extent a smaller chapter can do what a larger can't some times just cuz their marines know their job and are willing to do whatever it takes to do it....not go on and on and on about their chapter's honnor being ruined about a scorchmark on their power armor and then slaughtering their allies before going on a mindless headlong assault.

some chapters can even be Solid snake badass infiltrators if not better and can somehow infiltrate highly defended bases with running power armor, and then destroy the whole facility with just one squad. but the above is certainly a good and should be once perfected followed standard for writers to use in regards to semi-codex or fully codex adhearant chapters.