Some newbie questions

[Beorne]

I'm new to this wonderfully complex and deep game.
I have this game by genuine luck: I ordered Dominions 2 and they sent me this. I wrote Shrapnel the error and they sent me the right game. After some months of the awesome dom 2 I'v given a try to this game and I've found a true treasure.

Now I have some questions:
1) I've found tons of mods for this game, much of them very complex and full of features. Are there some mods that are used "by default" by almost all players? What are the most populars?
2) Is there a way to automatically update the ship designs with new components without doing this explicitly (and rename and make obsolete the old design)?
3) Is there a way to change the "colony type" after it has been founded?

Thanks!