There's a lot of things I'm hoping to see in PvP when it comes but there is one thing I really hope makes it when the gates open...
I would really like to see all resources generated by our main (safe) island to be used in the PvP area. Even right down to the sticks and stones. Pinewood planks and stones could be used for repair etc. Many of us will have invested 1 to 2 years into our main island by the time PvP comes so this would really bridge it nicely. I'm afraid that if there isn't enough that we can use from our main island over to the PvP zone it may result in a real disconnect, so much that it feels like 2 separate games. It would allow all levels to get involved. Lower level players can bring over supplies for repair, layout or to enhance structures etc. For players who went pure commerce and even a specialized type can be an equal contributor to the fight.
In the same way we use Scouts and Geo's, perhaps we can have Caravans to take supplies over to the PvP area. One player may bring a lot of stones to create towers while another brings bowmen to place into them. Could make for a real cooperative guild effort. I realize there will be special items which can only we gathered at the PvP zone but would be terrific if everything we make back at home can be brought over.
I also really hope that the PvP area is a very large single map carved up with each one having something unique to offer in resources, advantages/disadvantages. Seeing a map that is color coded based on guild/owner could play out real well. To reduce server load you could let's say have a dozen or so countries as one group located on a single server. You can tell visually very easily the groups. To take troops from one continent(server) lets say to another you would need once again to use the Caravans. Continents can be visually separated by water even slightly is fine and just use a simple bridge image to show that a Caravan is required to get there.