Spent just about all day since noon on this (It's now 8:05). The ppi is increased to a solid 144 as opposed to the old 100. I figured out how to use the Displace tool to achieve more or less the effect I was after with the mountains. I'll be playing around with them a little bit more. Still working out a good method of showing the political borders, but all I've come up with is the super-subtle glow around the landmasses you can see in the first version.
I decided to use edited RPG Maker VX Ace tiles for the city symbols. I'm much happier with them, if only because they fit the "grid" a little better. Also included the parts I had forgotten about in the past version, like the Phantom Woods.
I'm very interested in hearing peoples' opinion on this version, as I'm pretty close to getting exactly what I want here (planning on getting this printed on a poster from Zazzle, if I didn't mention that in the previous post).