As an aside, in the time between writing the first installment and this one, I have been to see PACIFIC RIM and it was pretty much everything I hoped for. Thank you, Guillermo, for keeping the nerd-faith. For any of my readers who haven't already -- see it. You will be happy you did.
I think the thing about the mecha genre is that it works very well as a side-light in a story that is explicitly about something else. The Robotech "Macross Saga" that so obsessed me at a certain age is really a soap opera set against the backdrop of an alien invasion / space war. Evangelion is about the psychological damage done to people in war.
Pacific Rim smartly builds into its mecha-mythology a technological requirement for (at least) two pilots in each of the towering Jaegers, two pilots that must explicitly have a close bond which allows their minds to operate in tandem during a mission. Although it is on the surface a story of the battered human resistance fighting a losing war against sub-oceanic giant monsters, it is about those close human connections -- a kind of ironic reversal of scale. In the midst of these larger-than-life battles, what really counts is the space between two people.
I believe I have heard that Wick's The Aegis Project includes this kind of intimate relationship at its foundation, with one player taking the role of the pilot and another taking the part of the artificial intelligence within the battlemech. This bond is for life, and if one of the two within the relationship is lost, it creates permanent damage for the survivor. (If I've got this wrong, let me know -- again, I've not read it, but I was following the pre-release hype with some interest.)
As I get older, I have found my relationship with combat in roleplaying games changing. Like most gamers, it was initially a major feature of games that I ran and games that I played. Now, I mostly throw it in as something to change up the pace or perhaps ratchet up the tension a little. I prefer my fights these days to be fast, so we can get back to the "good stuff" -- which, for me, is the interplay of characters and meaty dramatic scenes. I suspect that a mecha game would play this out on a somewhat larger scale; space battles would need to be fast and colourful, but not distract the game too long from the HTHD play we're looking for.
The game I pitched last fall to my group, DAISHO, was intended to be a game more about political intrigue than stompy robots (although it had those too). The idea was that the players would all be samurai for one of the aristocratic families in a galactic empire that resembled feudal Japan. The difference being that samurai would be explicitly mecha pilots, flying giant robots that were each styled after the animal which represented the aristocratic house. So a family with a crane as their symbol might have a "Scout Walker" style two-legged mech, whereas the turtle clan might have something heavily armored and slow. Towering above them all would be the "Toho" mechs, humanoid giants (similar to Del Toro's Jaegers) which each clan would only have one or two of... the sort of thing used to settle clan disputes in a duel of epic scope.
But again, all this was intended as colour in a game that would be similar in tone to Game of Thrones. The complex relationships within a family, who was sleeping with whom, and the succession of the empire would be more important than playing out elaborate orbital incursions by armies of giant robots. The title -- which suggests the combination of a long and short blade in combat -- was meant to hint at this matter of scale.
My group said no to it. But one day...!