Well, in this fanfiction, perhaps a plot point is Ichigo's struggle to control his power that goes beyond bankai. It could be like he has to face some inner demons or past traumas that are unlocked with this new power. Also, there might be a new villain or group of villains who are specifically interested in his new power, and they try to either steal it or use it for their own evil purposes.
In 'ichigo goes beyond bankai fanfiction', an exciting plot point could be the discovery of new techniques related to his enhanced power. Maybe he can combine his bankai - like abilities with some spiritual energy in a completely unique way. This could lead to some epic battles where he has to improvise and learn on the fly. His relationships with other characters, like Rukia or Uryu, might also change as a result of this new power. They could become more of a support system or have different roles in his journey.
One interesting plot point could be Ichigo's new powers and how they change his battles. For example, he might have abilities that allow him to manipulate time or space in combat. Another could be the reactions of his friends and foes to this new level of power. His friends might be in awe or a bit worried about his newfound strength, while his enemies would likely be more fearful and have to come up with new strategies to face him.