Generally, I'm fairly knowledgable about the 40k universe, and I like Dark Heresy a lot, and I'm just now jumping into Rogue Trader. I've got a couple ideas for some adventures, but my players asked me some questions that, frankly, I didn't know the answers to.
1) It is written in several places that Rogue Traders often command multiple vessels. Do the PCs start out with just one ship, or the one ship accompanied by several lighter vessels?
2) If a Rogue Trader has multiple ships that are his (or his Dynasty's, at least), do they all accompany him, or can he send out Transports on routine cargo runs on the trade routes he has established? And if the latter is the case, wouldn't they be relatively unprotected if they go at it alone?
3) If a Rogue Trader has multiple ships, are all the captains effectively Traders too, but without the Warrant of Trade? Do they all have to be PCs?
4) The crew of the ship they made is more than 25,000. That's a lot of mouths to feed. I don't know if overhead is an issue to be handled in the game, but how is a crew sustained during a voyage? Are there massive gardens or Soylent Green factories aboard?
5) The Captain's Cabin. My Rogue Trader Player wants to know generally how big a cabin he gets. I thought, given the size of their ship, a mini-mansion might not be out of the question. What is a common expected accommodation for the captain?
6) What about the other PCs? What kind of accommodations might the trusted retinue of the Rogue Captain expect? Given each individual career, I'm sure maybe the Navigator and Astropath Transcendant might have very different accommodations than the Arch-Militant.
7) How is a ship's crew comprised? With 25,000 or so, some are going to be in Engineering, some are Security, some are Gunners, Cooks, Medical, Chaplain support. Are there other departments?
8) With all these crewmembers, it seems as though the PCs will want to try to solve every hostile action or potential hostile action that isn't in space by sending down large detachments of "troops." What I'm asking is how do I get my PCs involved in something without it always being a surprise attack by some bold Orks that they would rather handle themselves without pulling a Zapp Brannigan and sending wave after wave of men at the problem?
9) One of my PCs wants to be a Sister of Battle. What role might she play on the ship? One thing to note is that there is no Arch-Militant, so my first thought was that she might take up that role, but I can't help but think that's not going to be a permanent position if the Adeptus Sororitas has anything to say about it.
10) Small craft? How many smaller craft might a Rogue Trader's ship have?
11) Going back to my Rogue Trader player, he wants his own harem. Would that cause him any problems with the Imperium in any way?
12) The subject of harems brought up the topic of women. What might life be like for women aboard the ship? My Sister of Battle player, a woman herself, offered up something interesting: that they see it as their duty to procreate for the ship (her words not mine). Is that plausible?
Just a few things to help flesh out my adventures. Thanks!