The capped view does employ marginality, it argues that the marginal benefit of something good like a friendship decreases if one already has friendships (as opposed to the first friendship). You seem to be arguing that the marginal benefit of additional units is constant and therefore one can just use arithmetic to compare these various scensrios to each other. But mostly you seem to be talking about the addition of years that one can enjoy those good things not the things themselves. (Also pleasure I would say is not something that contributes to well being but a component of well being).
The capped view does employ marginality, it argues that the marginal benefit of something good like a friendship decreases if one already has friendships (as opposed to the first friendship). You seem to be arguing that the marginal benefit of additional units is constant and therefore one can just use arithmetic to compare these various scensrios to each other. But mostly you seem to be talking about the addition of years that one can enjoy those good things not the things themselves. (Also pleasure I would say is not something that contributes to well being but a component of well being).