Keep in mind that none of us are admissions officers (or I think very, very few of us are), and that at best we’re just remarking on what we’ve seen on these boards and in our communities.
I’m going to remark on the bigger picture because your overall academic resume looks great. You’re maximizing your opportunities to the best of your ability and doing well. You are going to get accepted to some pretty fantastic schools. It would not be impossible to get into all of them. It also would not surprise me if you get rejected to a lot as well… but I do think it unlikely that you won’t get into a couple of very highly selective schools.
So, for your specific question on which one sounds better… I’d rather you ask yourself – which one you would rather do for yourself? Which one would get you excited to go do in the morning? To steal from Marie Kondo, which one sparks joy?
I don’t think it’s necessarily wrong to try to treat each EC as a stepping stone to something else, but you really should be careful on what you are doing and why? I’ve known many of my friends to chase one shiny accolade after another and end up as a partner of a very presitigous law firm, and then realize they never did anything they actually wanted to do.
Just make sure you’re being intentional with your choices - do they make you happy and fulfilled? It doesn’t have to be an either/or choice – you can resume build while still doing meaningful activities.
For your choices, I don’t think it’s predictable which of your options will increase your chances to get into Yale at least from our seat here. I think they both enhance your resume, so I’d just focus on which one will make you the most excited. If you get rejected from say Yale, you’ll never know why (it probably won’t be because you chose the wrong EC here), so assuming that, would you regret not pursuing a particular EC? I mean if you choose X, get rejected from Yale, will you be sad you didn’t do Y because it would have made you happier even if didn’t get you into Yale?