first, you must be at third civilisation level for them to apear. as in, you must be empire/confederacy then you might get a decission to reform a type of your soldiers. each type requires different buildings. iirc 3 baracks or 3 furnaces is for upgrading normal infantry. number of them doesnt seem ...

celts, italics, semites and greeks are just fine. germanics could use some more buildings (and a way to get archers early) but otherwise are fine i would like to see more flavour in other factions though. iberics are just celts, berber tribes have nothing original going on for them, dacians are fun ...

a few turns later they declared war

I have seen tar workshop. Its rare though. I have never seen synagoge/holy estate.