I'm stumped on a few things

Okay, been playing for about...7 hours now total, after a few false starts. I'm a Scavenger, done a few sectors, and just finished the first Challenge sector, so I'm feeling pretty good about myself, but some things about the game still elude me, since I can't find the answers anywhere else, figured I'd ask here, and see if someone could answer me.

1) If the Race has a + next to the Trade option on their screen, how can I find out what they want to trade? Or is that just there to say they'll trade with you period? Cause it always seems to be there.

2) Is there any way to increase the Structure of a planet from your end? It gets really annoying sometimes to have a good trade stop get destroyed because of constant monster attacks, even at Very Slow Pacing.

3) Is 16 the max cargo bay limit?

4) Does Technology follow me between sectors, or do I have to start all over? By this I'm asking if I should start saving those 'Technology' items I tend to find sometimes.

5) Are there any ways other than rumors to make two races like each other more? Not that those take a long time, but they are rather expensive to do in any sector close to your level.

6) Why do some Sectors have an $ by their name?

7) What is the max level for the ship, and what's the max level for command?(I know all other stats max at 250, though you can of course go more with crew and components).

I'm stumped on a few things