So, I was originally going to ask some potentially stupid question about how much Profit Factor is enough? You will always want more, and the doing more endeavors will gain that, but you reach a point where you might feel "big enough", and can make the rolls for more of what you want then you fail, even for cool stuff, but then I hit a different, maybe better, maybe just as dumb question:

Once you get your group to a certain point, how do you prep loot for an area? More to the point, I'll use my RT silly guy, Aedan Qel-Drake, for this example. Aedan wears BQ enforcer light carapace, has a good field rating item, a coat that is, for all intents and purposes, a Salamanders Hero Mantle, from DW, a BQ inferno pistol, and a BQ unique Eldar power sword. While some of the weapons might not be the best that I might choose, much of his gear is in some way iconic to or for him, and he's not likely to change any of it, regardless of "better options" he might find in some wreck.

Once your group gets to a point where they feel they've cherry-picked the ideal gear set for themselves, what's good to leave them to find? Certainly, another BQ plasma pistol is a great little treasure, but not worth a PF, maybe not even several crates of them, and the way sales work in RT is usually bulk goods that make even Sam's Club, or some gov'ts gag, so I'm not sure what they'd do with some of them, once procured. Another box in the hold might get another plasma pistol dropped into it, or you might prop it up on another table in your cabin, but that might not even be a show piece. As with Aedan, you (the GM) might even have something on offer you think is better, like a BQ plasma pistol might seem to be superior to a BQ inferno pistol, if only because RT doesn't use Melta, and the clip size of an inferno pistol can hurt, but if Aedan's Dragon's Ire is his iconic gun, he/I might not care. He might get ahead wearing that suit of artificer armor found in the Tomb of St. Cognatius, but it's power armor, for the most part, and might not fit under is spiffy coat. Have you run into this problem, and how did you endeavor to resolve it? It would be boring to find no loot, but equally so if you don't see any of that loot as worth using, and it can't be converted into money on the scale that a Rogue Trader and Co. care about. Thoughts?

I believe the trick isn't to give them stuff that is mechanically better than what they already have, or more of what they already have, but to give them stuff that is unique and interesting. Maybe something with a story.

This thread has some examples.

https://community.fantasyflightgames.com/index.php?/topic/131713-treasures-wonders-and-objects-of-ave/

The Imperial Double Eagle - It's basically an autopistol with the storm quality. It's the creating of a now dead magos who was hoping to create a compact but powerful weapon for tank crews and pilots that also didn't use archaic and expensive technology. He submitted the design but wound up accused of tech heresy and killed by a rival sect of the Adeptus Mechanicus over another project. He was later exonerated, but the design submission was dropped. In all likelihood there's no more than a dozen of these weapons in existence, created as models and test units.

It's not really all that great compared to a lot of stuff, but it's something unique at least.

Sometimes you can make PF level loot, or favor level loot. There are actually a couple of good examples of this in Dread Pearl & the adventure where you loot Vaal. "Datastacks of Navy records from the Crusade", "A still active cryotube with an ][ symbol on the side.", "A fragment of the Divinicus", "A Baneblade" are all could be worth a PF, or could be directly gifted to the relevant organization for a favor, which is a powerful tool.

I would also play with specifics. Don't think about weapons & armor, but utility tools. Even something as mechanically useless as "a watch that keeps perfect time and shows you sunrise, sunset, moonrise and moonset, regardless of planet. Nobody knows how it updates when you change planets." can be wonderfully entertaining to find.

Simple idea is- either give them stuff they can't really buy (because it's either something you made up or it's unique/near unique and they wouldn't bother to go out of their way to get it) or something that they wouldn't even have thought about themselves. Some examples of loot that me (and my friend that pretty much took over GMing) made:

-Vortex Torpedo- extremely valuable, and definitely not something they would've considered working towards.

-Archeotech heater- yeah - it made it significantly easier to create a colony on an ice world (it was potent enough to heat up a huge palace for hundreds of years).

-an extremely valuable bottle of wine, worth a point of PF or two by itself (we drunk it, of course.)

-A Land Raider. (In case you have never played tabletop 40k, it's the best tank deployed by space marines, and it's pretty much never seen outside of their forces. It's so tough that Blood Angels chapter literally drops it from a Thunderhawk gunship flying several hundred meters above ground level and it's undamaged.) We didn't actually get it... yet. We know where it is, though.

I like the suggestion of "something they wouldn't have thought of themselves." It's like getting the perfect gift for a friend, something they didn't realize they needed/wanted until they got it.

I try to operate on the rule of cool as well. It might be practical, it might not, it might be useful, it might not, but I always try to make it something cool. That's how I came up with the idea of giving them Robocop, a land squid, a hover motorcycle, a whimsically murderous eldar corsair, a bearer contract for best quality high provinder (such as the high lords of terra eat), and so on.