OP, what kind of riding do you do? When I was 15 to 50 years younger, 1/5 lb of rotating weight meant a lot to me, even though I was doing minimal racing and mostly Tues and Thurs World Championships six month each year. Notwithstanding the other benefits mentioned.
As Drew said, corrosion (and especially freezing) of nipples is mitigated by proper spoke prep when building a wheel. I have over 50k miles on different sets of wheels all with alloy nipples and that hasn't been a deterrent. I live in the SE and have stifling humidity and have had little NC (nipple corrosion). I suppose if I lived on the coast my answer may differ slightly. I do seem to corrode my handlebar stem bolts in no time.