This is a really good analysis, especially since I thought Esemjay was a big Civ V supporter. I'm not so sure the AI is as "fixable" as he says though, for combat at least. It will take a much more radical approach than a simple mod to fix. Maybe Firaxis will be willing to modify the 1UPT somewhat, but I don't think so, especially since it would be humiliating for them to do so.
I'm playing a game of Civ4 right now, and I'm leaning more and more towards the idea of "X Units per Tile".
During the course of this Civ4 game that I'm playing, I'm starting to realize where a lot of my issues are coming from. Civ5 maps feel smaller, because armies take up too much room; while Civ4 maps feel enormous because armies take up no room whatsoever.
I have had games where I had enough room in one tile that I started to wonder how they all fit there. As in... hundreds of units in one massive Stack of Doom. I feel that 1UPT was a leap in the right direction- but as with any leap, they ran the risk of overstepping the goal. And that's exactly what they did. Instead of 1UPT, units should be given a percentage of a tile, and you can stack units on that tile until it's full. Sure, it'll put you in situations where you have artillery protected by infantry... but that's how it actually works. Artillery isn't just posted up on a hill by itself with no protection; and the game should reflect this.
I'm confident that, given the number of talented and determined modders on this forum, a lot of the controversial steps that were taken by Firaxis will be fixed once the DLL becomes open-source.