My suggestions on the matter:
1. Do not allow opposing WvW servers to guest to the other servers. I would not put it past some groups to coordinate effort to ruin PvE events on another server they because they are getting hit with the “ugly stick” in WvW.
2. Irregardless of whether the issue is guesting or chest loot, home server members should get priority over guesters, PERIOD. I can’t even get events done on my OWN server. Just ridiculous.
3. My own personal suggestion, color code guesters names with a different color so that I can see who is a guest and who isn’t. I realize some people have stated that the influx is prior people on the server. However, I can tell you, that on my server, I have seen literally dozens of new guild tags roaming around. I have been on my server from day 1 and play pretty much religiously daily and do not recognize half of the tags I see now. So I actually do believe that guesters are a “contributor” to the issues.
Just my 2 cents worth. Peace.