Yeah, they kinda do. I haven't booted it up in a bit, but IIRC somewhere around 500 of my 700 slaves are in the suite role. I almost never actually do anything with them because of how much of a hassle the sex system is, but I like having them there.
I mean, yeah, they give more credits, but I've basically got infinite credits, renown, and honor at this point, so the only things left are to finish mopping up the galaxy and collecting interesting slaves.
I'm talking about the ship, which I think is named sword of entropy, not the weapon named eye of entropy that wipes out entire planets. The ship is just an op ship that, yeah, pretty much takes over any star system without ever getting damaged.
Again, I've got almost infinite money and I've maxed out all the research trees, so I just auto-buy maximum planet and station defenses and any assault by enemy factions does nothing but give me extra money and slaves. Your ships don't actually matter for defensive fights, only your planetary defense upgrades do.
Yeah, there is a sell all, but like I said, I like slave collecting.