First let me say that in spite of its flaws, I absolutely loved Civilization Revolution. Hate at me if you want, but that's where I'm coming from.
One thing I enjoyed about Civ Rev over Civ IV is that, while there were fewer options for leaders, every leader seemed to play much differently, at least in a more immediately visible way. Regardless of how the bonuses turned out in the end, everything just "felt" like it had more impact.
Take Japan for instance. I like the idea of the Bushido ability. It fits their flavor well and provides a nice combat bonus. But what happened to the incentive to build flourishing coastal networks, and go island hopping? Bushido is nice, but Japan could start in a desert area (provided that realistic food supplies are available) and not notice a difference either way. Egypt's Bonus and uniques make sense, but shouldn't they be more adjusted to desert life (maybe an ability to better work river floodplains for more food and some utilization of blank desert squares instead of the original +1 Food, Trade for all desert though?)?
Getting new abilities during different eras just made the game more fun in my opinion.
List here VVV for non-console users.
So, like the idea or hate it, I'd be interested to know if these modifications to the leaders are possible, or if they could be achieved through other means.
While thinking about how it may be implemented, I also came up with another idea. Assuming that research is easily modifiable, how hard would it be to introduce civ-specific techs related to history? Someone would have to come up with a set for every Civ, but I can't imagine there aren't some history buffs around here would love to propose historic events to be used for the tech options. For example, let's say you're playing Washington/America and you reach either either the industrial age, or the 1860's. A new set of options becomes available in the tech menu which are mutually exclusive, and have drastically reduced research requirements. You can research either Union or Confederacy. The war will give you a hit to your population in some way, but you will emerge with a powerful bonus depending on the historical outcome you chose. What if India was unable to gain full autonomy and the British managed to convert Ghandi's movement into a political puppet. There must be a decent selection of options for civil wars, leadership changes, and revolutions throughout the years to provide a decent selection to every Civ.
This would present players with a bit more late-game flexibility if things aren't playing out to the strengths of their chosen Civ.