I'm just wondering, has anyone experimented with tile sizes? One thing that bothers me about 16x16 tiles is that you can't put a line straight down the middle. You also can't divide it evenly into threes or draw diagonal lines from all corners without making an awkward 4 by 4 shape. Being able to divide in half is also extremely helpful and a double line doesn't matter as much with larger tile sizes, probably not at all with 64x64+. I made a diagram showing things, even though it probably doesn't really mean much.

I drew the separations for the ones I found interesting plus the standard 16x16 and 32x32: 27x27, 24x24, 15x15, 12x12, and 9x9. They may not completely make sense, but I think it helps illustrate the ways you can separate them. I could say in theory that 24x24 is probably better than 16x16, but I haven't tested it, so I was wondering if anyone else has any insight.