Is 16GB RAM "plenty?" I'm not so sure. It depends on what kind of development you're doing, what you're running locally, etc. My work laptop has 16 gigs hard capped, and I always wish I had more headroom. Obviously, budget matters, so that's a call for you to make, but 16 gigs is probably the smallest amount to call "enough" these days.
(Of course, it's also extremely easy to expand if you find you need more, so...)
He's already said he's retiring about three times. Then finds something he likes the look of and he's back. I mean, if he says it after every film, he might eventually be right!