With regard to "Exploration," I've got a fix in mind for that. It's an old idea of mine, that I've posted about before, to put a cap on the number of tiles away from you Civilization that your units can move, not just the number of tiles your unit can move per turn. This way, you simply can't move from one side of the map to the other in the BC's. Whether that's a hard cap or soft cap is debatable.
I think I used to called it "Operational Range" and it's basically a second kind of movement point. Each time you move a tile outside of your borders, you follow the usual movement rules so that you can only move a limited distance per turn, however, each movement also subtracts '1' from your OR. When the units OR reaches '0' a number of options are possible:
- The unit is transported back to the capital on the following turn.
- The unit is transported back to the nearest owned tile on the following turn.
- The unit starts loosing HP until it gets back to an owned tile.
- Etc.
As for the bucket-filling, that was also my biggest concern - that it's a necessary function of the game. So, for the mod, I was thinking that I'd just minimize the importance of filling the buckets by providing other mechanics that fill the bucket faster. It would cost so many points to fill the various buckets, that you'd rarely actually go through the the motion of filling one the usual way. One example of this already exists in Civ5, with the Great Engineer. The importance of filling the production bucket goes out the window when building a wonder if you have one of those handy - you simply build the wonder in a turn. Vox Populi's random event system is also another example of this, where the player is given a choice of responses and I could reuse that system, modifying the values such that they'd minimize the importance of bucket-filling. Of course, minimizing the importance of bucket-filling is just side-stepping the issue, not eliminating it.