I'm not thinking principe you are using is correct. Because Yamamoto was said to be on SWP level, but didn't make to list because he become soft. Yamamoto never intented to rebel.
Possibilities:
- Uryuu, he has something that can surpass Yhwach's powers.
- Jugram, he is holder of the key (that sent them to RR) and according to Askin he will be emperor before Uryuu, even thought Uryuu can surpass Yhwach, so maybe Jugram can as well.
- Urahara, smartest person around
- Kugo, he is like Ichigo Hybrid, we still didn't get his background.
- Tier, Yhwach defeated her, but why didn't he killed her?
- Grimmjow, Chad since I throw Tier here, why not these two XD
- Orihime, her powers are still secret.
- Tsukishima, from where he escaped when he was a kid?
- Ryuuken, anyone wonder why still he didn't appear in Quincy arc.
Maybe Uryuu and Jugram could be. There are two SWPs on Shinigami's side (Ichigo and Zaraki) and one neutral (Aizen), if there are two on Quincies than fights would be balanced.
Possibilities:
- Uryuu, he has something that can surpass Yhwach's powers.
- Jugram, he is holder of the key (that sent them to RR) and according to Askin he will be emperor before Uryuu, even thought Uryuu can surpass Yhwach, so maybe Jugram can as well.
- Urahara, smartest person around
- Kugo, he is like Ichigo Hybrid, we still didn't get his background.
- Tier, Yhwach defeated her, but why didn't he killed her?
- Grimmjow, Chad since I throw Tier here, why not these two XD
- Orihime, her powers are still secret.
- Tsukishima, from where he escaped when he was a kid?
- Ryuuken, anyone wonder why still he didn't appear in Quincy arc.
Maybe Uryuu and Jugram could be. There are two SWPs on Shinigami's side (Ichigo and Zaraki) and one neutral (Aizen), if there are two on Quincies than fights would be balanced.