As for the best ship build, I think it really will depend on what you want to do. Just some examples of situations that might influence what parts you decide to use:
  • You might have a ship that is dedicated to sector unlocks and is making quick trips to sectors with potential. In that case, the best we can recommend with the present knowledge is a great rigging to reduce time.
  • Perhaps you are hunting for dusk leather, there are several sectors in the same area that give a chance to find it. You'll want to make sure you have an adequate hull for visiting as many of these as you can in one trip.
  • If it turns out that retrieval does contribute to better retrieval levels and a better sector ratings, you will want to make sure you have the best aftcastle on your ships that are still gaining ranks.
  • Maybe you are looking for some gathering/crafting materia. There are certain sectors with a gathering/crafting materia theme. If it turns out that surveillance/favor does contribute to your chances of finding a second item per sector, it might be smart to bring along a good forecastle for trips like this to improve your odds.

With the present content, once you've found all the sectors and leveled up your ships, there doesn't seem to be any other reasons to send airships out besides item gathering, so I'm guessing that will influence players opinions about which parts to bring. Perhaps with future patches, stats will have additional effects! \o/

One thing I'm looking forward to is getting more data that isn't so uniform on stats. As Nyalia has mentioned before, most people have upgraded their ships with the latest parts that become available, which means that most of the stats are fairly similar (multicollinearity). Since the best airship parts go well beyond the capacity to equip all of them at once, we might get more people with varying levels of individual stats. This type of data is a lot more likely to help us answer questions about Surveillance, Favor, and Retrieval. So if you do your own experimenting with advanced parts, be sure to add your data to the spreadsheet! \o/