Didn't try to anser all of them, but...
2) Divining rod? No.
3) More room for engines, cargo, supply storage, weapons...
6) Don't think so, and no.
7) No, send 'em anyway. If he get's tired of getting duplicates maybe he'll put one up somewhere.
8) Random
9) The Minister of "Doing it yourself" is the only one I use anymore.
10) No. Unless you are playing agasint me, then yes they do.
11) You don't have to "activate" the scanner or anything, but you have to click on the ship to see it's design. Unfortunatly it does not save the design unless you actually encounter it in combat.
12) Yes
13) Pretty much. I think you are correct.
15) No
16) I think they increase the base damage, but not the tractor effect.
17) Yes. Depends on who you ask.