@bjango I think just working would be a good feature. This is what I see when I raise my wrist, and it stays like this until the watch goes to sleep again. (Series 10, latest OS)
When I installed the complication it showed the correct temperature. A few hours later it showed the temperature from when it loaded (tapping the complication updated it). Now, several more hours later, it shows what you see below.
@bjango I get that and can see your point. A message anywhere in the app would help, or even in the watch app somewhere.
That said, would a sub help with slow loading? It took over 4 seconds to launch when I tapped the complication (Series 10). Weather took under a second.
Also, a bit more info on some of the wider complications (like Photos) would be nice. Too bad my iStat sub doesn't carry over :/