Okay, so it's gonna be another few months (if not sooner) before the next companion after Amy/Rory on Doctor Who is announced and I'm going to take a wild stab and assume the next person is going to be female. Don't get me wrong, another male companion during Moffat's era is entirely possible/likely but here's a list of female actresses I think are possible/have been rumoured to play the next TARDIS occupant. If anyone wants, I'll do a male version of this list too.
Amara Karan: She's already played a character named Rita in the utterly wonderful The God Complex and unlike Carey Mulligan, it's more possible that Karan may return to the show, despite her character's fate. Heck, this show has a knack of casting actors in guest roles before having them play either companions or a Doctor at one point. Just ask Lalla Ward, Colin Baker, Freema Agyeman or Karen Gillan. Amara could easily reprise the role of Rita (via some timey wimey) or portray a totally different character.
Antonia Thomas: Already known to everyone for the last three years as Alisha on Misfits, Antonia's currently a little freer, time wise and as an actress, the girl has a certainly likability and presence about her. I could see her tonally playing a different character to the one that she's made famous over the last three years.
Imogen Poots: Imogen has the interesting advantage of previously working with Matt Smith on last year's BBC2 drama, Christopher And His Kind and the two of them had an excellent rapport with each other on that one-off drama. I think her and Matt working with each other again on a bigger show - the chemistry would be immense. A year ago, she would've been perfect as a younger version of River but I think with Mels in Let's Kill Hitler, that boat has sailed but maybe as a period companion, Poots would flourish.
Jessica Brown-Findlay: Sometimes I despise The Sun. It would take them to suggest the most excellent choice of an actress for the next companion, which probably means the chances of them actually playing it are non-existent. Jessica's a prime example of this. Yeah, she's one of my favourites as Lady Sybil in Downton Abbey but she's also been excellent in genre shows like Misfits and Black Mirror and I could just see her as a companion. Given her current TV commitments, it's bloody unlikely though, isn't it? Damn, because I really, really want her as the next companion now.
Miranda Hart: Okay, there's a reason behind this one. I'm not a big fan of Miranda myself but as Catherine Tate and James Corden have taught us, never judge a book by it's cover and there's a chance if Hart ever got cast as a full time companion, she could be good. The Doctor thrives with older companions (Jack, Donna and River attest to that) and Hart was supposedly rumoured to feature in The Doctor, The Widow And The Wardrobe, so even if she doesn't get cast as the next companion, I think it's almost a fair bet that she'll appear in the show within the next two years.
So that's my list of lovely ladies who could be the next TARDIS occupant - what are yours?