[@Jinxlynx] Not sure about co-GMing, but since you're asking for help about how the game ought to go, here's a few questions: is there any restriction on what House a given character can come from, such as Imperial or AdMech allegiance, or whether they come from a Great House? Must all Houses be canonical, or can players come up with one of their own?
Likewise, is there any restriction on Knight patterns? Are Cerastus Knights allowed? Questoris Knights? Are we allowed to come up with our own unique Knight patterns? Or do we have to stick with just the main notable Knight patterns?
What sort of rank should each PC have within their respective House? Are standard Knights and Knight Apparents the given, or can some people take up arms as Seneschals or even Barons?

These are the questions that must be asked. I'm sure there's more, I'm just not sure what they are.