yes there are basically 4 types of "male" units that can eco/fight. You have your regular CS, same gather rates as vanilla (except a few new civ bonuses) Then you have your Levied citizens (Perioikoi for sparta fall into this category even though they were citizens, they have a different label but same stats) 5% faster gather rates -10% dmg and -1.5 of hack/pierce resistance. Then you have your serfs (mostly just stone throwers) They gather 10% faster but do -15% less dmg and -5 range and 10% less accurate. Lastly you have Helots (Slaves, really only sparta at moment and rome has a p3 swordslave) they are 15% faster gather, but -20% less dmg, -5 range, 20% less accurate, less health....  Just opens up more ideas/strategies etc.

IMHO, auto-queue should go.

I don't think there's such video, here is Eco guide: (Tho watching ValihrAnt is also good idea, agree with Stockfish)  

Does he have some where he explains stuff? I'm not sure watching him doing ~hundred clicks/second will help much...

Hello @Ludwik, first of all welcome to 0 A.D. i recommend you to see some ValihrAnt videos on YouTube. I am sure you will learn a lot of him. Here mates gave you good advices that I suscribe. I would tell you also to start focusing on eco playing alone, becouse it is the main reason you lose vs the AI. I am 101% sure that is the reason. Make fields closest to cc so you dont lose time walking to gather resources. Also storehouse nearest to woodline possible. Try to avoid iddling time... As you can see this game is about using your resources with the maximun efficiency possible and lose the less time always. Also Never stop producing units. Try this and you will see you kick izi the AI I hope to see you on 1400s soon!  If you see me on lobby ping me if you want more deep advices!

Just tested historical mod playing Spartans and they have a similar system with their Women, Helotes and CS: Women and champions can be trained in the CC while Helotes are trained only in a separate building. Champions cannot do anything except fighting (but they do it very well obviously ), Helotes can both gather and fight. Oh, and CS are trained in separate camps. Seems logical and diverse enough, at least for Sparta.

I sent it for the reasons given by @Radiotraining The bugs are some missing textures and missing tooltips warning that I can't find.