Hmm I actually was doubting between those 2 for my alt as well

. But well, since you are powerfarming your alt you shouldnt worry to much about getting party's easy or not.
Anyway 1on1 I prefer rogue, because I like the weapon switching play style better. I also absolutely love high crits. Wiz/clerics gets relatively stronger when they obtain better gear. But still not quite as strong as a rogue in 1on1 I think.
In group pvp they have totally different roles IMO. Where a wizard is mainly there for dmg + mana drought and kb ( sometimes). A rogue is mainly important for scorch + interupts. Rogues are annoying as hell. 1 Rogue can keep a cleric from casting for a long time. Its also verry funny to receive screens or buffs from an enemy due to scorch.
They also have the option to deal EXTREMELY high situational physical dmg(prick+crit+desperate dagger), rogues can kill ints really easy. Wizzys deal way more splash dmg/constant dmg and their dmg is magic based.
However, in most partys theres a guard tamb+mana tamb+ magic dance up. So you will deal less dmg then a wiz. Rogue's tend to not receive to many defensive buffs cause they are purestr afterall so they are really vurnable. Desperate daggers+fence makes a tank died verry fast to. Bless + desperate doesnt stack to well. You wont have these problems with crosbow extreme though. So due to the image people have off rogue's, you will get less buffs resulting in less dmg/survivability compared to a wizard.
Anyway I personally went with wizard. I already have a main tank/cleric, so when I want 1on1 pvp I just log on him. In group pvp with kb+stun+bleed+kd etc im already pretty annoying. And well I just wanted to try an int based char for once. Aint enjoying wizard to much anymore though, at first I loved the nukes but now they look really boring

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