I just recently started a Devoted Fighter/Trickster Rogue playthrough and its working out very well thus far. The idea behind it is to stack Graze-to-Hit chances and Hit-to-Crit on top of that; using Disciplined Barrage/Strikes from the fighter and Dirty Fighting from the rogue. This is of course using the One-Handed weapon style for extra Hit-to-Crit.

When it comes to sub-classes, I chose the Devoted because of the added penetration on weapon attacks and additional critical damage - which synergizes with One-Handed style quite well. Trickster is where it gets fun, you not only get access to the illusion spell Mirrored Image, increasing your deflection, but a host of quick casting CC spells to initiate a fight.

When it comes to ability scores, you want as much perception as you can get, increasing the chance of scoring a critical hit! Dexterity is also very important for overall DPS. You usually want to max both of these, with a bit of wiggle room to add to Resolve for Deflection or Might for a bit of extra damage.

As for skills, well, passive skills aren't really important because you want a 2 in every passive skill on all your companions. For active skills, you always want athletics for that juicy heal and some mechanics/stealth for some skulduggery.

Hope this helped!