Okay, so, first off, if you're an Orihime hater, please, don't even bother reading this, I don't need no notifications filled with sass and B.S. Also, if you're not up-to-date with the current arc, or at least up to volume 60 this may contain spoilers. (I've personally only read up to volume 60 for the pure fact that I like to save my eyes for the artwork until I own it for myself, however I do read summaries and stuff so I'm caught up with all the hype and stuff, so I only know the major highlights such as Komamura, Kenpachi, and all the stuff that's been happening)
ALRIGHT, now that that's out of the way, time to get to the real topic. So basically, you know how Sado had gotten his Brazo De Gigante thing(Sorry if I slaughtered the name :P)during the Hueco Mundo/Arrancar Arc? Well, I think that Orihime could have some extra level of power too, they say that Sado's powers are like a Hollows, but later on more like a fullbringers, and then we see Xcution get their "true fullbring" which is their second form of power. This is scattered I know, but I just trying to get something going here. Shikai, Bankai, First release second release, Fullbring, True Fullbring, all these powers have two forms. Orihime's power's if you look at their potential, possibly makes her one of strongest character's for the pure fact her power can increase to any level depending on her emotions, if she has all the anger in the world(which she could never have because she's too kind) her Koten Zanshun, would crush Zaraki like a fly. But the way she is now, she would be crushed like a fly as her power wouldn't even compare. Her powers are immensely strong but she just isn't the kind of person that is able to use them to their full potential because she's not the fighting kind of person. So, here's my theory, basically, there's this recurring theme I've noticed in a lot of manga/anime and stuffs, something to do with like, 7 heavens. My theory is, if Orihime does have some other form of power it would involve in each part of the Shun Shun Rikka getting their own purpose instead of combining their strengths to preform a technique. There's only 6 of them, but possibly Orihime could count as the 7th "heaven". Her powers are originally seen by Ulquiorra as a rejection/transcendence of time and space/gods will but it's later discussed by Aizen that her powers are simply the rejection of an event that is either past, present or future (Soten Kisshun heals, Santen Kesshun protects, Koten Zanshun attacks.) what if what Ulquiorra saw, or thought he saw, was actually her second form of power? (Also quick note, each time she uses her techniques she chants "I Reject" to empower it, similar to how even when in Shikai, some soul reapers like Renji will still say "Roar Zabimaru!" to add power their attack or something like that.) If what Ulquiorra saw was indeed a second form of power, it's possible her "Bankai" could be the actual control of space and time or even the fifth dimension (the space time continuum is made up of 4 dimensions, the first 3 being space the fourth being time, correct me if I'm wrong, please) either way this is just my theory sorry for it being all over the place, but if TL;DR here's it in a summary.
If Orihime has a second form of power like Sado, it would have something to do with time/space and possibly 7 different skills each representing a different "heaven"(like an opposite to the seven deadly sins). If anyone has any ideas or would like to elaborate, please reply and post your ideas/theories because this is something that I've wanted to discuss for awhile now. Anyway, thank you and have a nice day! ^u^