I just wanted to share my personal experience when going from a Watch 7 alluminium to a Ultra 2.
I did not have any issues with a regular Watch in terms of battery life since I do not monitor sleep with my Watch. I usually ended my day with 40% battery and put the Watch on charge at night. But wow, its a big difference. Now i charge my Watch to 80% and after two days its around 30-40%, so it should go for 3 days with a full charge no problem. Great to be more flexible around charging!
I also notice the screen is much easier to see in the sun of course because of the 3000 nits display.
Its small things, but the battery life is the most important thing for me, its a game changer. All in all very happy with my switch. It took a little while to get used to the added size and weight going from a 41 mm 7.
I hope Apple finds a way to make the regular (Sx) watches last long… maybe by making them a bit dumber like cheaper smartwatches when needed, like when traveling. As much as I want longer battery, I am unable to like the Ultra design