Yes, maybe "beatable, probably close to 100% rate with strong play" was not very accurately put. I think it's over 90% though, and the 10% losses come from getting pounded on early. I got declared on only once and it was by an AI with a very weak position (Nap).
I am not very efficient with rally points and stuff and I'm just way too careful with my empire management. I think I need to improve that to make it bearable.
Hours of my life are not worth anything, so no worries.Hours of your life will vanish on these settings. One pic of yours all the AI have red fists by their names. You do get some insane stacks but if the AI are busy destroying eachother you can likely ignore their stacks. As you suggest getting peace becomes a lot harder. Once you are up to 30-40 cities when should get easier.
Have you considered any strategies to help unit movements. I think you can set up rally points. Plus queue builds using alt key so you don't need to keep micro builds.

Yes, it's more opportunistic and chaotic and definitely requires different skills, which is refreshing.I don’t think these settings really reward longer term strategy and more your ability to react to opportunities presented by the chaos. It still requires skill - and I can’t really comment on whether it’s more or less skill - but different skills.
I think corner of the map is easiest, but of course depends on the amount of useless tundra, which might be an issue on Lakes. Again depending on the map layout, but many times on crowded deity maps you will see no barbs at all. It can play quite differently on emperor, but at least you are pretty much guaranteed to win GW if you need it.do you really think the middle of the map is so bad? "Lakes" wraps horizontally so you will always have neighbors east and west. If you're near the north or south edge that's a lot of useless land with lots of useless barbs.