Three things I learned from the BETA that people should take on board.
1. Condition damage avoids toughness and armour. Do not underestimate this! It murders Guardians.
2. (Credit to Calypratus from "The Unnamed") You can place an Armour Rune on your Breathing Mask.
This means you can have seven runes not just six. They might fix this
but who knows.
3. When out of combat you can swap out a Focus or Horn, give youself the
speed buff, then swap back to your shield/torch/axe/sword or whatever
your offhand is normally. This means in SPvP you can get around from
place to place quicker.