Crit or condition damage for WvW?
A condition damage build will kill people more then fine in WvW atm
But you can tbh. build both a power/crit build, and a condition damage build, both see it’s use in WvW at the moment, but I’m my personal opinon the condition damage Engineer is the strogest of the two in a solo roaming perspective (which appear to be what you are talkig about)
WvW Roaming movies!
I prefer condition damage in WvW because it has a simpler playstyle and can also be much tankier than a crit build (i.e. to do max direct damage, you need power, precision, and crit damage, which means you won’t have any toughness or vitality). Condition builds can max out condition damage while still having enough precision for procs as well as substantial toughness and vitality.
Also, most people in WvW haven’t figured out that their builds need some form of condition removal, so that helps.
For gear, make sure you do daily/monthly for laurels. Ascended stuff is just better, obviously, but doing 1 monthly and 20 dailies for an amulet will also save you the 3-6 gold you would have spent making or buying one. If you go conditions, the karma vendors in Orr sell rabid everything, which will save you a boatload of gold. Of course, you can also map complete/dungeon run for gear as well.