I strongly suggest Rao mentions 'We want to do regime change on systems hostile to us' and a quick summary of the whole end-game in 'Finale' where they need to convince worlds to join up based on their political stances. This is NOT expressly mentioned in the adventure, but it certainly is the goal of the whole scheme from the start -- don't just spring it on the players in the final chapter.
Also, Endie (I am pretty sure) made up some resources for playing around on Drinax to recruit Vespexer tribes -- some of whom are less than enthusiastic about folks from the Floating Palace. That might be good filler / pacing material for the players. I also think it happens to be a good place to introduce Prince Harrick -- and if you want a little delay before Oleb & Rao trust the player characters with the (figurative) crown jewels of Drinax, then having them do a good job here might help.
And having the characters spending some time at the Floating Palace gives you a chance to introduce the various NPCs that will be important later -- Kasyil, Thao Poloc, Sal Dancet, Lady Hil, Admiral Wrax, Rachando, Chieftain Galx, & etc.
One option you might have is swap their ship -- Wrax has designs on the Harrier, and a lot of Drinax's resources are going to be poured into fixing it up. If it takes a few months to a year to get it fixed up, the players can be given a tramp freighter that was the property of some unfortunate who ran afoul of intrigue related (maybe Rachando did not want the competition) poison. They get some time as Far-Trader flying pirates themselves, with a healthy respect for anything that may carry a Barbette; and later have to do some politicking to upgrade to the Harrier & reinforce Wrax's bad opinion of them.