i say eng is best in pve. put all attribute points to int nd u will b alive spamming empathy nd transference. bt ur eng will b mana starving from lvl25-lvl40. after tht u will hav no problems either on health or mana coz of implants nd weapons.
my eng(46) has 9mana regen nd from rev skill +1 mp regen buff it adds up to 10 mp regen.
so my mana is nvr dwn while doing any maps.