I don't think I've ever been recognized for being SE when I am flying Y.
Upgrades are nice. Best perk of being an SE. That said I'd really prefer SE benefits to more practical or noticeable when I'm traveling in Y. I don't mean drawing attention to me -- but really, if anything would make an overall improvement to my wellbeing, it would be improving the experience in Y for SEs, since that's the least enjoyable at present.
(I say this because I'm stuck on a 3+ hour Y segment on Rouge in a few hours and I'm dreading it.)