No. The implementation is probably easy. The problem is that this would be a massive gameplay change.
First, it could affect the balance between the different civilizations. I can't name any specific problem right now, but big changes like this tend to have unintended side effects. For me, this would mean that I'd first have to identify these (possible) problems, which is hard, given that I never play multiplayer, that I'm not that good at the game, that only part of the playerbase actually gives feedback here, and, finally, that even if I get feedback it is often hard to judge, or even outright contradictory. All this is the reason why I generally try not to touch balance, except in obvious cases. Note that I would probably handle it differently if I had a larger and more active playerbase and had more time to mod and play myself, or a co-modder.
Second, and this is the more important reason: It is not clear whether your change actually makes the more fun, or less. To me, it sounds like an interesting solution to an actual (albeit, to me, minor) problem, but it definitely still would be an experiment. And I don't want to do experiments in this mod, for basically the reasons I already mentioned: An experimental change should ideally be tested thoroughly my as many players as possible that are willing to report problems, and, ideally, I would react quickly to fix those problems and iteratively we'd get to a point where the new feature works well (or roll everything back eventually). It would not work well with how I do things currently.
What I want that is that each version is a small improvement over the previous one, and people can be sure that the last version is not fundamentally broken in some way. That's why I focus on bugfixes and interface improvements.
Anyway, as always, if anybody wants to do a fork or Modmod or whatever that implements that sort of thing to try it out, I'm happy to answer questions if any arise.