How about implementing the ever-popular battle royal mode in GW2?Teams of 3 or 5 battle (or maybe solo) it out in a part of a WvW map, for instance? You start with the gear, build and everything that you already have in WvW (so it differs from other versions in that regard), and collect reward-tokens (or something) found on different locations. If you defeat someone you steal 50% or so of their tokens (so you get to keep some even if you loose, seems popular in GW2)? After the match the tokens can be exchanged for something. What do you think...something "fresh"? :)