The SE is my first ever Apple Watch, bought the SE because I didn’t know what to expect, or how it would benefit my life.
But I absolutely love the Apple Watch. In hindsight i should’ve bought the series 6.
But in my opinion the SE is great for the price, and I will only upgrade when it’s old and not functioning how it should any longer. Like your series 0.
I don’t have a reference point, but the SE is snappy, and everything works like a charm.
I just wish Apple would come with an equalizer for music, in the gym I only take my watch and headphones, and the music sounds not as good as when I play it on my phone.