Since Senna looks like perma ban material with her e ability make her open for both teams
How about on release, instead of her being permabanned in ranked because only 1 team can get to play her: If senna is open both teams have the right to pick her, making it a fair game because of how disgustingly broken Senna e ability is If senna is banned then no team gets to play her, but this option will be much less if both teams have the right to play Senna when she is open.
i predict Senna will have 95%+ ban rates on release, just for her e ability, and it is not any other part of her kit that is problematic, her ult is broken but it isn't game breaking.
, who was designed without weakness, heh) and they need time to experiment with the champion to do all that.