Personally I don't think the Control centre etc needs anything really happening to it, of course a better battery/camera is always welcome and I'm sure there will be some smallish upgrades to both in the 16.
Would seriously love to see a Flip or Fold iPhone but I doubt it'll ever happen.
Phones in general are just so boring now and they have been for sometime. I've been a iPhone user since the 3G was released but I have been quite tempted lately to try the Samsung Fold etc just because it's different but then I do soon realise I'll have to deal with Android
and soon find myself sticking and (hoping) that the next iPhone will be somewhat interesting/worth of an upgrade... I haven't had any reason to upgrade my 12 pro max yet, still going strong and have had 0 issues with it since getting it on release day.