Im new to this game :)
Welcome. Let me say 1st, this question has been asked over and over, so let’s summarise it briefly: The optimal weapon set for open world PvE is: sword/pistol//shortbow. Gear – Power main stat, precision and ferocity minors (Berserkers). Trait build – I think standart at 80 is 5/6/0/0/3, or 5/6/0/3/0(while you level – crit strikes 1st, then deadly arts). Utilities – mostly signets, maybe shadow refuge too, daggerstorm elite. My personal suggestion is – just explore all lvl 1-15 maps to 100% 1st while testing different weapon sets, getting to know how the weapon skills work exactly (and how the fields/finishers from some weapons interact). Just to clarify something though – sword/pistol thief plays much like a straight up fighter – standing and fighting in the open. The only difference between this weapon set type of play and a heavy class is – you rely on your blinds from the black powder and pistol whip evades to mitigate the incoming damage, instead of tanking it like a champ.