As I was reminded recently, one problem I've often had for Rogue Trader void conflicts is that the Imperial Navy isn't very scary. Indeed if you run them directly as presented, they're not much of a threat to any Rogue Trader, who has the distinct advantage of having a PC or Fated NPC command crew. I wanted to make some adjustment for this in a logical & fluffy manor that didn't simply resort to adding fated NPCs to every Navy ship. Enter the following rule:

Command & Control: Imperial Navy vessels have an officer core and chain of command a private vessel could never gather or sustain leading a unceasingly practiced crew. Navy vessels counts as having a PC in every ship role. In addition, they may perform as many Extended Actions as desired.

The result of this rule is that the ship is typically rolling at least 10 over it's already high crew skill. It can also take advantage of every form of roll-boosting pre-activity, often providing another 5 to 20 bonus. This should make it clear to the players that if it weren't for their PCs exceptional ability, the Navy would toast them. And in some cases may still toast them, particularly if they're out-matched for tonnage.

It seems like a very reasonable method to me. I've used the ship roles for NPCs in the past. I always give my rival RT figures a couple Fated Sidekicks and a few named NPC that fulfill the ship roles. I suppose I'd do the same for the Imperial Navy, just never had a group that decided to measure themselves up against the IN...yet.

I'd have no problem with my RT frigates beating up an IN frigate and I'm pretty sure my IN cruisers would kick the crap out of RT frigates using the above method. My IN vessels always have a few GC or BC components and a couple surprises.

Player: "What! That Dauntless has torpedo tubes?!?"

GM: "You asked which class of Imperial vessel in your cogitator banks it matched, and that's what your cogitator said. The Seneschal says it's not technically a Dauntless. It's a Dauntmore. She tells you it was a class made in the Zippity-Dooda Sector about 1500 years ago from some questionable STC blueprints. Roll for your turrets."

I don't mind the Imperial Navy as written being not very threatening, because in the Rogue Trader setting the Imperial Navy officers are the people the Imperium didn't want cluttering up their borders, or are on punishment detail, or were politically unwise or committed some sort of mistake that isn't punishable by death/execution/demotion, but is the equivalent of being transfered to Alaska.

Everyone competent in that region is on Passage Watch duty to make sure Chaos doesn't spill out of the giant Warp Storms, or has been re-routed for the eternal Achilles Crusade.