1) Yes
2) No. With so many people dumping trophies on you while you are away, by the time you want to start raiding again, you'll have 250+ trophies and will need to spend at least 10 minutes to get your trophies below 200 before you can even start looking for a raid-able base. Not quite efficient unless you plan on sitting in front of your device for over an hour to raid.
3) Spells really depend on the base that you are attacking. But from the replays I've seen it's either 3 rage, 2 rage 1 heal or 3 lightning to take out 1 Air D. (The base design of the defender will determine the spells you bring).
Here are several TH8 mass dragon attacks on different base designs that might help you decide what spells to bring.
https://www.youtube.com/user/3StarsC...on+Clan+War%22
Good Luck!

