Boyfriend told me he wants a watch (like a rolex?) when he gets married, in exchange for the wedding ring. Something to be passed down through generations, along with the ring.

There are tons of good watch brands out there who are classic and long-lasting. Like with an engagement and wedding rings, you need to sit down together and discuss budgets.

. A commitment piece and a promise. My acceptance would be the equivalent.

I don't really understand your line of thinking here.... the whole engagement process/meaning of rings etc. have changed quite a bit in the last few decades and engagement presents for men have become very common.

Why? Because if this is the way things are... then I think for having kids, he should buy me a tummy tuck, breast lift and laser scar removal.

I really don't understand what having kids has to do with the things you mentioned.