[Suicide Junkie]

Armor is much cheaper than shields to research but quickly maxxes out on the damage absorbed per space on the ship used.
Emissive is still useless. Organic is uberpowerful as long as you give it time to store up some regen points before it gets hit.

2) Depends completely on your play style.
eg: hermits would make good use of religious, for all the defensive & infrastructure bonuses.

3) Typically, building numerous construction bases around your homeworld is reccommended.
Other people will have more to say on this.

4) Good sites for what in particular?

5) Start a PBW game with "for beginners" in the name, and you shall find many.
6)
If by that you mean installing mods or shipsets, they are very much worth it.
Making your own is also very rewarding.