I've got an F5 and it is absolutely full of gizmos. The meter is arguably the best that Nikon has ever produced. I can programme it to have all sorts of custom menus and do all manner of tricks. Y'know what, I've loaned to a mate of mine and I now use my F2S and Nikkormat FTn instead when I want an SLR. For me , there's nothing better than a match-needle or a couple of little red LEDs to tell you it's just about correctly exposed. Then you can + or - to get the effect you want.
Putting the little fella next to a window and, perhaps, having a nice big piece of white card to use as a reflector - to push some light back into the shadow areas - will produce immeasurably better results than any flash - even if the flash is bounced off ceilings / walls. Flash is, for most people, just a bit too harsh for portraits and it kills mood.
Flash tends to be used in studios because it's extremely controllable and helps the photographer to get razor sharp images - which is not always what good portraiture is about, IMHO, unless you want it to look like something out of "Hello!"
The FM2n will also save you a lot of money (purchase and also batteries), be a lot more portable and save you having to read "war and peace" user manuals.