1) Rocket pods are for the instant-kill. If you crush the enemy on the first turn, it dosen't matter how long the reload time is
Plus, your fighters don't have to stay close and face the PDCs... They do all their damage up front, instead of being gunned down after a shot or two of the regular guns.
2) IDs will destroy engines. Armor and other components are ignored, although they only do normal damage to shields.
3) Yes. Toss on guns and shields, and the planet can shoot back at the enemy. Platforms will be destroyed first, before any population loss occurs.
4) It depends on the AI, but if you stay out of their way, and if they're already at war with someone else, they will tend to be friendlier towards you.
5) I personally loathe to use robominers, and prefer to StellarManip my way to 100% breathable, optimal conditions and 255%+ maxvalue planets, even when its not practical.
Robominers are effective, but I just don't like them
When you do use them, DON'T mix and match miner types. If you have all mineral robos, then the organics and rads value won't decrease, but if you have even one miner working the resource, its value goes down by 1% per turn.
6) There are settings and options to toggle, animations, fast combat, etc.
Its definitely not practical for large combats, and you can't use it in multiplayer unless you're doing it HotSeat.
You should definitely get some practice with developing good strategies for your ships, or you'll be at a disadvantage when you play against other humans.