I was supposed to do this when the new event dropped but uhhhhhhhhhh
I decided to count up the amount of Event 3☆s and 2☆s every girl has. 2☆s may not give a lot of BP but they're an easy way of filling missing character-attribute slots for event bonuses. Though with the new bonus changes, that might not matter much anymore.
Note: I'm not including 'Runっ♪' in the hallway' because it's unreleased and therefore subject to change, in terms of event order or even the event cards. If nothing changes, Himari would be the event 3☆.
As of August 31st 2019:
Number of Events - 89
Kasumi - 4 (3☆) and 3 (2☆), Total: 7
Tae - 3 (3☆) and 3 (2☆), Total: 6
Rimi - 3 (3☆) and 2 (2☆), Total: 5
Saya - 5 (3☆) and 1 (2☆), Total: 6
Arisa - 4 (3☆) and 3 (2☆), Total: 7
Ran - 5 (3☆) and 2 (2☆), Total: 7
Moca - 1 (3☆) and 3 (2☆), Total: 4
Himari - 4 (3☆) and 2 (2☆), Total: 6
Tomoe - 4 (3☆) and 5 (2☆), Total: 9
Tsugumi - 4 (3☆) and 6 (2☆), Total: 10
Aya - 5 (3☆) and 4 (2☆), Total: 9
Hina - 5 (3☆) and 0 (2☆), Total: 5
Chisato - 3 (3☆) and 2 (2☆), Total: 5
Maya - 3 (3☆) and 4 (2☆), Total: 7
Eve - 5 (3☆) and 3 (2☆), Total: 8
Yukina - 2 (3☆) and 4 (2☆), Total: 6
Sayo - 4 (3☆) and 3 (2☆), Total: 7
Lisa - 5 (3☆) and 4 (2☆), Total: 9
Ako - 2 (3☆) and 5 (2☆), Total: 7
Rinko - 5 (3☆) and 4 (2☆), Total: 9
Kokoro - 5 (3☆) and 4 (2☆), Total: 9
Kaoru - 4 (3☆) and 4 (2☆), Total: 8
Hagumi - 5 (3☆) and 2 (2☆), Total: 7
Kanon - 3 (3☆) and 3 (2☆), Total: 6
Misaki - 4 (3☆) and 5 (2☆), Total: 9
PoPiPa - 19 (3☆) and 12 (2☆), Total: 31
Afterglow - 18 (3☆) and 18 (2☆), Total: 36
PasuPare - 21 (3☆) and 13 (2☆), Total: 34
Roselia - 18 (3☆) and 20 (2☆), Total: 38
HaroHapi - 21 (3☆) and 18 (2☆), Total: 39
I would have an opinion, but I'm planning to do something similar for Gacha Cards in the future, so I'll leave it as that.
I'm also unsure whether I should update this post as new events release or wait a few months and make an update post.
Why did I say I was gonna do Gacha Cards as well? Can't wait to do the same tedious task but with 3 rarities and a whole lot more cards WOOOOOOOOOOOOOOOOOOOOO