8 ages of Pace was awesome...before R&F. I think it needs some tweaks now to be adapted.
Historic Speed is a nice concept (normal production speed and 3x techs and civics times) BUT it isn't well balanced yet.
I'm playing a Large Map with 13 civs and 17 CS with Historic Speed right now. I changed some values (techs and civs x2 instead of 3, eras x2, dark/gold treshold +20)
The map still gets realy crowded with units but it's already more playable. I've had my very first Dark Age ever. Huge wars abd battles like i've never had. Really challenging for the moment.
I'm playing it in "Demi-God" mode (Smoother Difficulty 1.4) and it looks like I'll never be able to win that game, but I'm having some fun
(almost all civs have 2500+ armies, Korea has 450+ beakers/t @turn 250, other civs between 270 and 120, I'm struggling with Mongolia, around 7 techs behind)
There are other simple mods called Erax2, erax3,... but I never tried those. I think they just change the era min and max turns.
"Take your Time x2,...." only change the civics OR the techs costs.
You might want to try all those 3 together.