For what it's worth, while the in-game AA really does clean up the jaggies nicely, it also blurs/flattens some of the textures. You can see this effect it if you look at the characters' outfits, particularly around the neck area. With in-game AA off, you can see clear detail and the folds/ridges of the outfits have a distinct 3-D appearance. With in-game AA on, the texture details are somewhat blurred and the 3-D effect is flattened out. It's pretty subtle, and I had to look closely to see it, but it's there.That blur extends across different textures in the game as well.
So far, my best-looking results are with using VSR (game set to 3840x1620 on a 3440x1440 monitor), in-game AA off, and adaptive multi-sampling anti-aliasing at 8x in the driver. I'm not sure the driver anti-aliasing is working completely as intended, but there is a reduction in jaggies barring a few odd pieces of environment. Character models are sharp, though. This is on a 6800xt through the AMD drivers, so I'm not sure what options Nvidia users have for forced anti-aliasing.