I'll recommend using RS, Veil, Aimed and Nox in Wt4, Traps won't be particularly useful til you hit elites so it's more important to dish as much damage as you can .
For traps and RS, I generally steer clear away from the bleed because I don't like the aggro but it could be fine in WT4 if the mobs aren't scaled too high :P
And as a side note, packs are futile in PVE in almost every single aspect as you have items called potions that can be purchased pretty cheaply and don't take up a skill slot
Note: Remember the Razor Shield bug when formulating your build!
GL ^_^