Sinister/Viper rune choice
According to the post on Death and Taxes, you’ll want to aim for full Viper gear with Runes of the Berserker.
http://www.dtguilds.com/forum/m/6563292/viewthread/15457607-dnt-engineer-build-specialization-update
viper with aristocracy or berserker runes will most likely be the new glass go-to if viper allows you to max out bleed and burn durations without needing to sacrifice runes and/or wrench nourishment (and even if its just runes).
aristocracy for pugging, when you cant depend on having 25 might all the time and need to provide at least some might to you team. berserker otherwise. nightmare + coral if viper gear doesnt let you max out bleed and burn durations, mixing in sinister to bring your durations down to only 100% exactly.
i havent looked at it much yet cuz gw2skills doesnt have the new stats up.
head here to discuss wvw without fear of infractions