Greetings Vinz, glad your back, and I hope the Empress and little Vinz are doing well. Just want to give you some input from some of the games I've been playing.
1) Barbs; Honestly, I absolutely love your barbs, and other than RI mod, they are perhaps the most frightening that I've come across in all my years of playing Civ. Problem is, the AI just cant handle them, or refuses to either tech for self preservation, or be an idiot and move out defenders at an inopportune time.
With RB off on Epic spd, I can lose between 5- 10 AI's. On Mara spd, bump that up to between 6- 12 ( I play giant maps, so there's going to be some variables).
With RB on; Heh, it's a blood bath. On Epic spd, I can usually count on loosing 10-15 AI's easy. On Mara spd, I can lose between 15-20 ( personal best was 24 out of 32 AI's).
Possible solutions would be for the AI's to actually realize that archery is survival tech ( despite what a lot of players say about it being a dead end tech, in your mod, it's necessary

) and they should research/trade for it. Or maybe tweak the AI's a bit that leaving only 1 warrior in a city is a really bad idea.
I'm really wouldn't want you to have to tone down the barbs, as they are sufficiently scary as is, but something needs to be done in order for the AI's to survive on giant maps.
2) AI expansion ( discounting barb nukage); Still on giant maps ( all I pretty much play), The AI's don't really seem to want to expand to much until about the end of the CE to the beginning of the ME ( with the exception of exp AI's). Now I realize that gold/upkeep plays a large part of it, but you'd figure the AI's would try to get at least 4-5 cities by then.
I know that as a human player, there's a huge advantage in being able to manipulate everything to the players advantage ( I. E. running 1 or 2 cities as gold farms using trade/wealth while the other cities do the work), But the AI appears to be more interested in troops than it is in creating a solid economy ( I'll see if I still have screenies to give you a clearer idea of what I mean).
3) Specialists; I think I may have mentioned this before, and if so, my apologies. But the sci spec gets really hosed until university comes along. I would recommend tweaking things a touch . For example; COE can give one spec. Libby can give 2, Uni can give 3 ( Obsveratory is fine at 1). This can also help out the AI quite a bit as well, and make TT a lot more in depth.
4) Spies; Ok, got to admit that this is a pet peeve of mine. But when playing on giant maps, its a royal PITA having to send your spies all the way back to the front lines, especially on water based maps. Yes, I know that there are a couple of modcomps out there that can alleviate this, but for those players who don't know how to add a mc to a mod, it can be a bit intimidating.
a) some additional spy questions; If I chose the promo to see hidden, how come it doesn't work to detect enemy spies? It doesn't work for snipers either. Additionally, if I have a spy in one of my cities as a counter spy, how come I can't use the sentry command? seems to me if im using a spy as a counter in a city, I should be able to have some chance of detecting an enemy spy.. Just curious.
I'll have more stuff later as I find my notes, those were the current ones I had on stickies in front of me

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I really love your mod bro, and it's always been in my favorite top 3. Glad your back, and I look forward to any updates you may have in store.
Drak.