@cromcrom
Well, first game done now. All worked fine (used english language instead of german right now, but'll try this one too).
Here are my comments...beware HUGE
Storyline:
In common all looked fine to me, lot of leaders and nations to choose from...lately in-game it looked other way. I've choosen Charlemange/Germany but got US flag and got me situated into the european culture group. No difference for me so far, so i played on with different flag.
First choice to research was sailing, as my settler started at the sea and lighthouse would be good choice to grow city. After few rounds i founded my second city at the sea but also in range of flood plains so my second choice to research was agriculture. Third city founded in the hills near river to gain option on metal later. Then it happened i ran into my first burnout and it took me about 20 turns till i learned that my first city isn't my Capital till i build my Palace there.

Ok, after loosing all my units except the first one's in city, got my research reduced to zero i wondered how to grow again. But the Palace and my sea-based citys helped me survive this. I researched archery to protect my new dynasty and went on.
Then i concentraded on road, minerals, mining and revealing marble and stone for further upgrade, while hording barbars tried to overwhelm me. Archers here aren't good for offensive play, as i got them with Drill I (Protection) but they do no good against untrained warriors except they are defending. Lately i managed to capture pirate city with 6 archers against 2 untrained and ran into complete economic collapse of my kingdom thereafter. So my struggle ended...
Anyhow playing gave lot of fun and here my comments on different parts that may improove the mod....
Leader Traits:
Leader traits shouldn't be choosen before starting game. Just choose your empire to state your cultural group and improove leader traits by technological choice either. Means, if you go warmongering, gain 'Expansive' or 'Imperialistic' by promotion...or if you choose to go Archery before any other wartech, gain 'Protective'....like this.
Other idea is, to just choose your nation and after researching kingdom you are allowed to choose your leader...wondering if this works.
Cultures:
Since European culture is usualy based on Greco-Roman culture i could not really understand that splitting-up, but it's choice of modder i guess.

I would have splitted it more basic into European, American, Asien, African and probably Polynesian and Arabic.
Anyhow, trade between different cultural groups should be more restricted, as they do not set trust in each other due to early incompability. The base idea behind is, that the reason that splitted the cultures up, is the same reason to prevent early trade. So, if you trade with nation from same cultural group, all is fine you could choose all options, while trade between nations from different cultural groups should be limited on goods while tech should be restricted.
What could open up this restriction is same believe as it opens mind toward the other culture then.
As a impression, think on early contact between Europeans and Chinese. The Europeans interest only was gold, silk, opium...while they treated China as a barbarian horde. Later since Bhuddism and other believes spread into Europe too, this view changed...
At same view is war between nation of equal cultural group, it is easier to gain tech by conquering city then as you have deep understand into each other. On the other side if you attack someone from different cultural group you just think of them as 'barbars' and do not learn from them that easy.
Economics:
- Turn 120 = Gold: +10 Research: 20%
- Turn 180 = G: -11 R: 0% => STRIKE, loosing all units
- learned that my first city isn't my Capital till i build my Palace!!!!

- Turn 230 = G: +15 R: 10%
- Turn 304 = G: -23 R: 0% => STRIKE, loosing all units again
- Turn 328 = G: -37 R: 0% => no way out of this economic desaster
- Turn 335 => no change in economical way so i abandoned game...
It is deeply needed to convert city production into gold/research/culture so you won't get busted without a simple chance to survive. In tech-tree i couldn't find any tech that brings city improovements to gain money...how to survive economicaly???
Workers shouldn't get disbanded, as you could not reach other economic level instead.
Units should not get disbanded all, they should get re-fitet into workers by chance. It is hard enough to loose improved units while having a maybe 1/10 chance to gain a worker out of it.
Combat/Units:
Ever planed to wreck 'protective' improoved archers (Drill I, City Defense I) against completely untrained barbar warriors?
Archer (Drill I) got 3.0 : 4.1 odd against untrained warrior => killed!
2 Archer (Drill I) got 3.0 : 4.1 odd against same untrained warrior => both killed!
Archer (Drill I, on hill) got 3.0 : 3.63 odd against untrained warrior, so i backed down and he was killed while attacking.
6 Archer ( Drill I) needed to attack 2 barb archer (city, hill, untrained) => 2 killed, city captured
Warriors shouldn't get upgradable to archers, as they are melee units. Otherwise u have to re-arange it into a untrained combatant that is able to learn into different combat styles. There is a mod out, that archers need own camps to train...something like this.
Tech tree:
I think the early choice what to research should lead into different basic technological orientation (BTO) of your culture. I'd spread them into 6 basic directions with direct opposites:
warfaring <-> economic
mass-growing <-> high productive
belive <-> science
So if you concentrate on warfaring techs, like mining, early training or else there should be a high risk to loose more tech from the opposite BTO. Basic idea behind is, that once you go into special direction in research it is more usual that you are stucked into this area the more you concentrade on it.
Let's say you try to get benefit from believe...historicaly in most cases early churches tried to downgrade science to gain more influence on the people.
Yes, it is usefull to go some steps into a BTO, but if you go too far it could be that you are no longer open enough to gain benefits from the direct oposits.
This could be a great instrument to direct research into mainstreams and if you limit yourself for a specialisation you have to be good in what you do.
Directly this could be a good tool for you cromcrom, to not have completely cultural spreaded civs which aren't longer able to survive against others.
Last point for now: Tech trade should only give back the option to research that tech, not directly hand over this tech. So...if you do other choice you may again loose the ability to research this. Tech trade would then be much more interesting...
Sumary:
I do like this mod...and after typing the comments i'll do another round of testing. It is just huge fun as you could not know what is necessary next and so you aren't doing all time same gameplay as in many multiplayer games usefull. Looking forward to see upgrades! Thank's for your work, cromcrom.
If i could give support, just drop me a note.