A Future Doctor: I've never believed that this show will ever do a female Doctor (Curse Of Fatal Death notwithstanding) and while Clara can certainly talk a mile a minute, I don't think that means she's Twelve in female form. And she's not the first fast talking companion we've ever had. Anyone else remember Zoe and Jo?
Another Incarnation Of River/Susan/Jenny/Romana/Rani etc: Why would she need to be any of the above? Romana and the Rani can be recast, Susan should only be returned if Carole Ann Ford is brought back and Jenny was a minor that should be reprised by Georgia Moffett if the character is needed. As for River - we have seen every version of the character we need to and her storyline is winding down a bit.
A Time Lady: Again, don't see the need for one, especially when the show can bring back characters mentioned in my second point and it would make more sense than having Clara being a Time Lady.
A Version Of The TARDIS: We've already done this storyline with Idris in Series 6's The Doctor's Wife, why repeat it with Clara? Besides if the TARDIS has to take a human form again, I'd rather have Suranne Jones come back for an episode.
An Offspring Of Any Past Companion Or Doctor/Companion At All: We've done this last year with Amy/Rory/River, in Series 4 with Ten/Jenny and even this year with the canon version of Kate Stewart, so does it really need doing with Clara? Personally, I don't think so. Plus, Clara/Eleven have flirted/kissed, so she isn't related to him.
An Agent Of Madame Kovarian And/Or The Silence: Been there, done that with River already to be honest. Let's not repeat it again. At a push she could be connected to the Great Intelligence or the Daleks though.
This might not sound like the most concise of debunking but I wanted to keep this straightforward to be honest. Basically, I think she's something/someone new. I also think that all three versions of the character we've seen in both Asylum Of The Daleks and The Snowmen are either the same person or aspects of the same person. I also believe due to the fact that she's been given the moniker of the woman twice dead that she won't getting killed off in every episode of 7B. She's also attracting all kinds of odd attention too and not just from Eleven, so that should be interesting to watch.
What are other people thoughts/theories on Clara?