From the vantage point of post iPhone 13 release, how does the 12 Pro look? Well in terms of design great, as that hasn't changed. Though at time the increase in size versus 11 Pro was a definite downgrade, a small increase in screen size and a large increase in feeling of bulk (thanks to square edges) were definitely worse.
The camera got a subtle but distinct increase in quality. Performance was barely changed.
The battery life has been pretty unreliable; definitely feels like 5G made this worse. The 11 Pro was remarkably reliable in this area, but with the 12 Pro I get to end of day running low (whereas on 11 Pro I was very often over halfway charged).
256GB was unnecessary; the baseline was 128GB which would have been fine. But saying all that, it is still one of the best phones out there, even if the 13 has obviously superseded it.
I think it is worthwhile reviewing things, as Socrates maybe said "the unexamined life is not worth living". Here I share some reviews that I think are of general interest. I try to keep things short and focused on what seems like the less obvious aspects. But I write many, many more using an app I made Micro Reviews. Using this app I capture reviews of all sorts of things, like books, films, TV, food, drinks, coffee and more. These reviews are largely intended to be private, notes to my future self. This guides future purchases and serves as a journal of experiences.
Micro Reviews uses Apple's iCloud to allow for data sync between devices, yet making sure your data remains private (unlike in many Apps the developer, in this case me, can never see it). With tags and categories you can keep your reviews organised. You can also search your reviews and export them to a CSV file (so you do things with the data in Excel).
Download Micro Reviews for iPhone, iPad and MacOS. (It is free!)
You can also learn more about Micro Reviews but why not just download it (it is free and a small install size).