ive played a marauder as my main, lvl 49 as of this moment, playing as Anni spec with quinn out at all times and i seam to cut through elite mobs easily, usually ending up most fights with elites 1-2 lvl above me with 80% + health, i dont know if your doing something wrong with your rotation but the marauder seems fine to me. the only thing they really need is a pvp cc