OP, I think you're focusing too much on the "check-in 60 minutes before your flight" thing. While it certainly sounds like EWR was a slopshow that day, I would have expected that given it was 12/24 and the weather was bad. I know I often get those "it's going to be busy at the airport so we suggest you show up 3-4 hours before your flight" emails from UA, which for the most part I promptly ignore. Like you (and probably 90% of Flyertalkers), I know my way around most any airport and have all the cards and statuses that help expedite things. The only time I prioritize low-stress over max-efficiency (as bmwe92fan so aptly described) is when I'm traveling someplace like a vacation that has either limited flight options to get to and/or a big consequence to arriving late. The other thing I avoid whenever I can is checking a bag, but again it's those special vacation trips when I'm most likely to need to.

It sounds like the only thing you could have done would have been to spend the night at an EWR hotel so that you could have gotten to the UA check-in desk even earlier. UA rebooking you through FLL and on a competitor's connection seemed like a good accommodation, and it was just dumb bad luck that your flight to FLL got cancelled and you ended up stranded. And them giving you $150 travel credit and 10k miles seems like a very nice gesture.

If this had happened to me, I'd be frustrated too and probably wanting more. But sitting here as an impartial observer, it seems UA did enough and you probably should have gotten to the airport sooner. I see shared blame, and the way things stand, shared responsibility.