I wouldn’t worry about not being over the moon... I mean, if you woke up this morning and your beloved 6S had a brand new battery in it, a much better camera, more RAM, more storage, the fastest mobile processor on the planet, and suddenly supported wireless charging- would you be happy or sad?
I feel like it’s a no-brainer that you’re going to be well pleased with this phone!
Haha, I think you're underestimating how much I love my 6s (and my headphone jack!). If I hadn't stupidly upgraded past 10.3.3 a few months ago we wouldn't even be having this conversation. :-(
One big data point for me is battery usage with the Podcasts app, if it sucks as much battery on the SE as my 6s then the likelihood of return shoots way up.