Glad to see that Clannad was the finisher. My day has been made.
Might try this out over the summer. Not gunna lie though, im kinda scared
I believe Clannad/Afterstory with maybe the exception of Grave of the Fireflies had more sad moments throughout the shows entirety. The reason I have never been able to put Clannad as my number 1 is it was given more episodes so to be fair I've tried to look at the most powerful emotional moments in each show, I must say (without any streaming knowledge of newer or other shows)
Air(3), Anohana(2),Clannad(3), Clannad Afterstory(4), Angel Beats(2)
Rumbling Hearts(2), and Kannon(2) are all pretty strong contenders if you look at from that prospective. Furthermore, the top three(maybe because I'm a man) Air(the goal walk, Rumbling Hearts(mayal's goodbye), and Clannad Afterstory with Afterstory having arguably one the greatest if not thee greatest emotional scene("sunflower scene") in video media ever.
*disclaimer this view does not necessarily reflect the opinions of the members of Otaku Spirit*