Board Thread:Suggestions & Comments/@comment-24652145-20160204225112/@comment-4800771-20160205224448

This is related to the definition of mainstream. What's mainstream in Japan is not the same as in the west. One Piece isn't even close to the other giants of anime.

https://en.wikipedia.org/wiki/List_of_anime_series_by_episode_count

I wouldn't advise you to work on any of those long series. It's not worth it. Just work on things within your preferences.