Starting from antiquity to the future era has a certain charm.
A certain charm ? I would call it amazing, at least at the beginning. (granted we grew accustomed to it, hence the need to make it feel newer and different, something to underlines more the pass of time, something that makes the story renewed, underlined and re-hatched - I don't think putting an emphasis on eras, especially with civs flat choices, do nearly as much enough for it, I would even say that splitting the game like so has the contrary effect : too much min-maxing in my soup*)
We have though reached the very point that when we arrive there needs to be someone there. We play to find them, and we start new games to find them and we are looking so long we are very tired.
What do you mean ?
* : How would I do it ? By making numbers more realistic maybe, like instead of 10 pop it would be 1 million, things like that, and by making the size of cities particularly less linear, with deceases and migrations more important.
I would shift apart the center of the world, from Africa, to Mesopotamia, to Greece, to Rome, to Europe, to America, to globalized ideology blocks and after the fall of USSR emergent superpowers like China and other "dictatures" that doesn't encompass the Western way of thinking. Of course this is terrible in the perspective that "all people are equal", and that there is life elsewhere than in those "centers" (that, therefore, are disputable, where goes Persia, India, Egypt, Medieval/sooner China ?), but after all you don't have/can't be them everytime. Maybe culture and tourism would be a way to exist in the "half" world. (as to the tier world, they could try alternate paths like in Africa, if we let them be) Something like that,
potentially. (centers could be totally different compared to reality, but we need a firm mechanic that simulates this, like Golden Ages always tried to achieve, or unique units for warfare. But those golden ages should be rarer and lot more powerful) Obviously that's still a Western point of view, when we are obsessed with world supremacy, but Asia often fought for unification that was a goal in itself, and that also could be a mechanic that is shared by everyone. (like conquering neighbors culturally linked, with religion-like cultural expansion early and converting everyone around to our culture, that we, that said, have appropriated from someone else. Conquering a city/camp/tribal village/town with our culture would grant advantages.
(I don't know if the paragraph above makes for a "re-hatch" of global history though. Meh I wrote it so I let it there)
Just my way of playing.
People on this forum (at least the vocal ones!) rarely seem to enjoy all three of those! 
