• How does your progress through the eras feel? Is it too fast or too slow?
  Way to fast compared with Research progress. Research Progress feels about right. I think that Era and Research Progress should match. 
• Do you feel your research progress roughly matches your progress through the eras? Does it match what you would expect for a game meant to last about 300 turns?
  No, not at all. For me, Progress trough Eras is way to fast compared with Research Progress. 

• How do you feel about the speed of population growth?
  In the first 50-70 Turns ok. But especially in larger cities and later eras too fast. Pop Maximum of City did not matter at all for me because too high. 
• How do you feel about the value and the growth of the different resources (Including Influence)
  For everything: In the beginning ok, after 100-150 Turns or so everything grows way to fast. Cities and whole Empire "snowballs", at least on medium difficulty
• Are religions still to powerful, or are the bonuses at a more appropriate level now?
  No Religions feel alright for me. Immersion is the problem with religion, not the bonuses.
• How does the neolithic era feel now? Can you still grow your population too quickly?
  Growth is still possible, but it seems more balanced now.

• How does your progress through the eras feel? Is it too fast or too slow?
  Way too fast compared to Research progress, and way too fast compared to our abilities to build and leverage the unlocked infrastructures.
• Do you feel your research progress roughly matches your progress through the eras? Does it match what you would expect for a game meant to last about 300 turns?
  No, not at all. Progress through Eras is way too fast compared to Research Progress. 
• How do you feel about the speed of population growth?
  It's too fast. I was obliged to focus on infrastructures that provide food bonuses otherwise the people was starving. 
• How do you feel about the value and the growth of the different resources (Including Influence)
  It looks good, but since our progress through Eras is way too fast, it's hard to say.
• Are religions still too powerful, or are the bonuses at a more appropriate level now?
  Religions look good to me. I can't compare to previous opendevs as it was my first one.
• How does the neolithic era feel now? Can you still grow your population too quickly?
  It looked good.

• How does your progress through the eras feel? Is it too fast or too slow?

Era progression is fine, unless you are far behind.

• Do you feel your research progress roughly matches your progress through the eras? Does it match what you would expect for a game meant to last about 300 turns?

No, research is far too behind era progression.

• How do you feel about the speed of population growth?

It felt natural, love it

• How do you feel about the value and the growth of the different resources (Including Influence)

Way too much influence production since Medieval era and fort. First two era have sufficient production rate to allow interesting choices.

• Are religions still to powerful, or are the bonuses at a more appropriate level now?

Felt appropriate.

• How does the neolithic era feel now? Can you still grow your population too quickly?

Maybe need a little tiny drop in food gains to hit that sweet spot.

Suggestion on technology advancement (several people on the forum have already introduced similar idea).  

So, as long as particular technology is not revealed by any faction, its costs say 100% science. At the turn following the turn of revelation, the cost of the technology would, for example

1. drop to 30% for factions allied with the revealing faction and have science agreement with it    

2. drop to 40% for factions allied with the revealing faction

3. drop to 50% for factions that have “Trade everything” with the revealing faction A    

4. drop to 70% for factions that have “Trade luxuries” with the revealing faction A         

5. drop to 80% for other known factions    

6. drop to 90% for factions in war with the revealing faction    

7. remain 100% for factions not yet in touch with the revealing faction       

For example, if a faction is allied and scientific agreement (see percentage listing under 1) with faction which had already researched particular technology its science output for the technology modifies by 1/30%, in the other words by 1/0.3 = 3.33. If more than one faction have researched the technology, the science output of the acquiring faction would the one with higher modifier. Science output for the technology could be additionally increased depending on the number of factions already having the technology. Some benefits mentioned above are reversible and can be easily lost if a faction, for example, breaks the alliance (or scientific agreement...etc.) with its “donor.”  The faction's science output for the particular technology goes automatically down next turn.

The feedback implemented this way should significantly reduce huge technology gaps between factions and result in much more technologically leveled game. It should even mitigate technological differences between difficulty levels of the game itself. The leading edge of the technological progress would practically remain the same with respect to the game progress. The rest of factions can keep up much faster and get their respective era stars for it. Potential wars would be waged with equally strong units on both sides. Leading factions would be discouraged from over-investing in science unless they really need particular technology– nobody wants to pay huge science cost to be the first to research the technology unless really needed. Yet, stronger science infrastructure would, in the case of war, be a significant advantage over opposing faction as it immediately allows much faster technological progress.  

How does your progress through the eras feel? Is it too fast or too slow?

This time I played on lowest and mid-difficulty level (I think 4th). For balanced gameplay, progress through eras feels slightly too fast. In my opinion the most important thing is to get all eras to be leveled regarding number of turns. If necessary I suggest, along some other people here, the increase in the number of era stars needed to advance to next era.

Do you feel your research progress roughly matches your progress through the eras?

For balanced gameplay my feeling is the science always lags behind, regardless of difficulty level. However, by focusing on science, the technology tree can keep up with eras. Bigger problem is huge difference in researched technologies between factions. It may be addressed by lowering the cost of the already researched technologies based on diplomatic relationship with the owner of the tech and (or) the number of factions already mastering the tech.    

Does it match what you would expect for a game meant to last about 300 turns?

Actually yes. It will be interesting to see how much use of contemporary era units will be there.

How do you feel about the speed of population growth?

It is well balanced.  

How do you feel about the value and the growth of the different resources (Including Influence)

Influence is well balanced (together with influence-based faith bonuses). No chance of expanding your empire too fast. You have to focus on influence. That's good. Same goes for Stability unlike in Victor open dev. Production, Science, Money looks ok, as well. However, I noticed that I dominantly build cultures' special districts and rarely regular districts (e.g. I almost never ended up building market district). It may be a good idea to reduce the impact of special districts and increase the impact of regular districts.

Are religions still to powerful, or are the bonuses at a more appropriate level now?

It is balanced now.

How does the neolithic era feel now? Can you still grow your population too quickly?

At game difficulty level 1:  11 -12 tribesmen

At game difficulty level 4:   8 - 9 tribesmen

Later, half of the units were used to increase city population.

Personally everything seems balanced but I still wish you could pick from other religious tenets from the beginning such as monotheism for example

The AI pulls way ahead which makes the overall pacing feel off. Research also seems to lag behind era progression pretty heavily. In general I would like the game to last longer but I imagine that will be an option at launch.

Here is information about infrastructure cost, which may be good to look at since that impact the economy of the game Infrastructure cost