Not gonna talk about if the atmas are good or bad content, just gonna leave some tips here, if you do less than 12 fates in 1h you're doing it wrong, if you wait for a fate to pop you're doing it wrong, certain atmas are known for being hard to obtain, the ones dropped in areas with beastmen quests, there are more fates and occur more frequently, but the drop rate seems lower.

But if you're tired of the atma farming, i'm sure there will be more walls for ppl who is not whiling spend a lot of time, the first one after the atmas will be the materia part. The way SE is handling the relic quest chain makes me think it will be if not the best weapon one of them, nothing we should expect to be fast and easy, and if this is SE's idea, i'm sorry but i don't want it broken by complains, aim to something else or accept it'll take time, may be years for a casual player.

This said, i have my pld atma weapon and i'll do it again for the nin, no matter how much time it takes.