in 1e, the big advantage of darts is the multiple attempts to strike. Since M-U's have a terrible attack matrix (truthfully it's not much worse at 1st level than anyone else, but it is pretty terrible by 5th), gaining extra rolls is very valuable to eke out some damage.
That said, having some ability in melee is good, though frankly, most characters should be using pummeling attacks until higher level/specialization kicks in.
That said, having some ability in melee is good, though frankly, most characters should be using pummeling attacks until higher level/specialization kicks in.