So... I'm really tempted to do Navis Scion, from the Cassini house as described in the Navis Primer,, but for that concept, i'd rather be from a Magistral House. Can I create an equivalent from an homebrew lineage, as in, the same with a different name on a Maigstral house ?
So you want the House Cassini specific abilities, but stacked on a Magisterial House rather than Nomadic house ‘chassis’, right? I see no problem with that. Do you want to include the inter-house rivalry (the Nemesis part) ?
I've been been a player from day 1 in RT, and mastering a PbP RT campaign from rank 1 to 6 for three years , in which there is a huge focus on space battles. Don't worry about the ship part, I'll handle this. 
I’m looking forward to some starship combat
The RL Rogue Trader group I usually play in kinda shies away from ship-to-ship combat, due to liking character combat more (we’re all long time D&D players) and due to the ship we’ve managed to build being somewhat on the overpowered side (pretty much obliterates anything that’s not built to combat it specifically, or is elder frigate level of fast).
Considering the Overlord, a good one is the plasma drive, as I don't see the plasma drive refit being an easy one to do in game. The teleportarium is very good, but too much prone to abuse, so I try to avoid it when I play. (When I master, that's an other kettle of fishes )
100% agreed on the Teleportarium. Is probably the worst written piece of gear in the whole game IMO. Without limitations it’s abusable as hell. With the Into the Storm limitations (one use per session) you might as well not have it, because 90% of the players end up reading ‘one use per session’ as ‘only use when shit really hits the fan’ so it’s usually kept in reserve. In my group we ended up homebrewing some teleportation hazards tables and lifting the usage restrictions, so that teleporting blindly is quite risky, but teleporting with a homer is quite safe.
Another nice piece of archeotech that I like is the Energistic Conversion Matrix. Speed for power is pure gold, especially on larger ships
It’s your call though, of course. That device is nice for the RP implication and for offsetting the morale penalties for poor-quality components.
Some questions:
1)Does the Hatred (Psyker) talent apply to ALL Pskyers, or just un-sanctioned ones?
2) How does starting equipment work? I guess we get one "free" aquisition, but do we get to test for others, or is it just that plus whatever is in the "starting gear" section for our career?
3) I'm planning on going into the Drusian Adherent or Red Consecrator Alternate Advancement Ranks. Will the fluff requirements be possible? Or would it be advisable to take one of them now, since they're available at Rank 1? I'd have to give up starting with Dodge and Charm, but I'd get to start with Flame proficiency and Peer (Ecclesiarchy and/or Inquisition), which sounds fun, or Command and a bunch of Hatreds.
4) Any advice for what I should take with my Pressgang skill?
Numbered for convenience:
1) I’d say all psykers, since there’s nothing in the rules . Psyker hatred has pretty deep roots in the Imperial Creed. Sanctioning makes psykers tolerated, not liked.
2) You get the starting gear, one free acquisition, and that’s it before the game starts. In game you can make acquisition tests for more whenever it’s reasonable to do so.
3) I can’t find any specific fluff requirements for Drusian Adherent. Am I missing something? Anyway, you can do it several different ways: put the requirements in your background and either take the alt rank at rank 1 or later (since you’ve already fulfilled the requirement) or fulfill them in game (they will be possible to fulfill in game if you guys head in that direction).
4) I’d wait with that until you see what other people are playing in more detail, and then fill in what’s missing. If nothing particular Pilot (personal) is always a good choice, as Jump Packs and Hoverboards (and Harelquin Flip Belts) are awesome.
Also, since pretty much all of Harald’s ships seem to come equipped with Barracks
There’s no official mention of how many troops a Barracks component holds (apart from ‘thousands of troops’), I’d suggest we go for 10% of the ship’s crew (so an Overlord would have room for 10k armsmen). How does that sound?
If I missed any of your questions please let me know.
