1. I don't remember any big bugs on either HoT or PoF launch, so there is no reason to wait.
2. At launch I focus on the story and will go back to finish the maps afterward.
3. Stay away from social media, don't pay attention to mapchat. If you move quickly enough there won't be much chance to get spoiled.
4. I'm mostly a solo player, so I don't much care about the Guildhalls. I will try to solo the new hall for my bank guild, to check the scaling for small guilds they were talking about on stream.
5. No, I will leave the strikes for last.