Lancer in my viewpoint is used as a heavy DD such as a cross with dark knight in the strength sense and samurai in the TP burn. When I am fighting nms I like to use a full STR build with 170+ and the rest is accuracy. I find myself doing as much damage as an archer with buffs (ferocity/raging strike/keen flurry or hawks eye). If I get my WS in the right spot of the BR I can do an easy 900+ dmg doomspike II on great buffalo or ueraus. When fighting the group nms I like to equip a lot of low tp/AoE moves to spam and throw in buffs every now and then. I find it taking down the off mobs a lot quicker than having a group on each off mob at a time.

As of my soloing, I keep it standard with strickly lancer ws's and abilities to buff dmg and drain hp, and ofcourse the standard conj spells for protect/shell/spikes. One more thing I forgot to mention was that it seems to be better when sticking with speed surge for nms and party and life surge for solo since it drains HP on ws's making it next to never needing to cast cure.

Some of the traits I have found incredibly useful for this job are the 10% healing bonus you get from pugilist, out of sight from archer which lowers enmity for those of you who do not know, and the movement speed + for active mode just incase your healers can't reach you in time for a cure while fighting nms or party mobs in threat of getting AoE'd on low health.