Unless you are going to go for an F4 or F5, support for all the metering in AF-D lenses, not to mention autofocus, will be incompatible with your other needs. But then metering the night sky won't work anyway. For long exposures a camera with mirror lock up is ideal. That includes the Nikkormats/Nikomats and the F series (though the F itself makes you waste an exposure). Best bet would be an F2, F3, or Nikkormat, with the latter being much much cheaper. Night photography is pretty much a dedicated use for my Nikkormat Ftn at this point, as I use an FE2 or F3 or a pair of F100s for everything except time exposures. But it was my primary camera for 15 years, and my Dad's for a 15 before that and there is little it can't do.