• "Empire 5" is hard to remember, why not refer to empire leaders rather than empire names? They all have names per the game setup screen that would be much easier to remember than an integer/color. (Especially since the color isn't displayed on some notifications)
• Tenet, luxury, and some other descriptors are unclear about whether they stack or how they stack; half the level one tenets are "+1 resource per follower on city", is that +1 per global follower on all cities? +1 per follower in the city where the followers reside?
• Similarly, I couldn't tell whether I was properly interpreting the Public Ceremonies or they were just... really really bad. Near the end game, it was asking for 800 production for two influence points. Was that two points total (if so, what's the point? I could just build more commons quarters for less) or was it two points per turn for some period of time? The Parade was particularly confusing; does that experience bonus last some number of turns? Forever? Can I do it more than once?
• The "Force surrender" screen was very confusing at first, with some things greyed out without explanation, the colors apparently showing who currently controls that territory but still being hard to interpret (especially in the case of just "Outpost")
• I can't tell what people are buying from me on the trade screen; are they currently using my silk? I don't know.
• Reveal capital didn't seem to do anything.
• Similarly, I had trade maps with some empires at various points but it didn't reveal their entire territory to me, leaving some areas blank and apparently missing their actual city center.
• Tech osmosis events seem to sometimes proc without there being an option, and when you click on the "beaker" icon it just disappears; I later realized that I was getting a flat science boost with no choice from them by hovering over the icon before clicking it, but still felt unclear.
• Could use more clarity around where districts could be placed; I especially wanted more clarity on the Baray as I had several locations where I couldn't put them but wasn't sure if it was a bug.
• Starting wars seemed to proc a "Religious Conversion Started" message but the "location" of the message was just at the far southern edge of the map, not centered on a landmass.

I strongly support the first point... it was a little frustrating to have to go dig in diplomacy to see who the notification was about.

UX-wise, i would add the fact that "Faith" (or was it "Fame") in a very light creme colour, on white background is barely readable.