So I was looking at the characters that have reappeared after Wano and decided to make a list going over who Oda has and hasn't brought back. Also made a bonus list as to what characters he has yet to bring back, and I'm pretty sure the first three there are the ones he's keen on the most:
Hancock
Teach
Shanks
Crocodile
Law
Sakazuki
Garp
Marco
Kuma
Kuzan
Kid
Buggy
Borsalino
Sabo
Mihawk
Sengoku
Dragon
Rayleigh
Lucci
Vivi
Ivankov
Issho
Tashigi
Bonney
Koby
Pudding
Perona
Shirahoshi
Killer
Rebecca
Wapol
Sentomaru
Neptune
Spandam
Koala
Tsuru
Sai
Shakuyaku
Helmeppo
Hina
Riku
Imu
Weevil
Cobra
Charlos
Leo
Bonus: Characters that have yet to reappear in the story after Wano:
Doflamingo
Moria
Smoker
Enel
Bellamy
Bentham
Shiki
Magellan
Jozu
Bartolomeo
Hatchan
Baby 5
Chinjao
Urouge
Pekoms
Vista
Karoo
Gin
Kong
Hancock
Teach
Shanks
Crocodile
Law
Sakazuki
Garp
Marco
Kuma
Kuzan
Kid
Buggy
Borsalino
Sabo
Mihawk
Sengoku
Dragon
Rayleigh
Lucci
Vivi
Ivankov
Issho
Tashigi
Bonney
Koby
Pudding
Perona
Shirahoshi
Killer
Rebecca
Wapol
Sentomaru
Neptune
Spandam
Koala
Tsuru
Sai
Shakuyaku
Helmeppo
Hina
Riku
Imu
Weevil
Cobra
Charlos
Leo
Bonus: Characters that have yet to reappear in the story after Wano:
Doflamingo
Moria
Smoker
Enel
Bellamy
Bentham
Shiki
Magellan
Jozu
Bartolomeo
Hatchan
Baby 5
Chinjao
Urouge
Pekoms
Vista
Karoo
Gin
Kong
