The Troughton/Jamie McCrimmon dynamic was very good.

I did love that but in general I do prefer the Doctor/one female companion/one male companion dynamic.

And I can agree with that. I would prefer, however a Hartnell/Steven/Vicky dynamic as opposed to a Smith/Amy/Rory dynamic. Basically, I just don't like the sexual tension oozing out all over the place in my Doctor Who (not that I mind that per se, I loved Torchwood, but I prefer it in Torchwood and not in Doctor Who).

Lucie Bleedin' Miller!

Seriously, I don't if this is a troll answer of not, but Sheridan Smith already plays a companion (one of the best too) in Big Finish's stories for the Eighth Doctor; Lucie Miller. I highly recommend giving them a listen since many of them are easily some of the better stories in the series.

As for the topic: No matter who the actress is, I'm really hoping she plays someone who is not a modern day Earth girl. I want someone from the past (not WWII or Victorian), from the future (at least 100 years forward), or from an alien planet. I really want there to be companions like that, preferably alien ones. From the introduction of Leela, to the departure of Turlough, the Doctor had at least one nonhuman companion, and I would love it if we got back into that habit.

Totally agree with you except *cough* Leela is human*cough*

Yeah we are overdue a non present day female companion.

Or even a companion who could be living in Britain but isn't actually from Britain though.