1) What would your new 8th or 9th Doctor be like? Who would you cast, and how would he be characterised?I'd cast someone mature with proper acting chops...maybe Jared Harris.
My Doctor would be hard to pin down. Ebullient one minute, and brooding the next. He'd have that lovable uncle feel to him Tom used to have, as if he's carrying you on the journey with him, rather than focussing the audience's gaze through the experiences of the companion.
He'd refrain from acting like a God and be more modest about his abilities; facing more conundrums and difficult choices. He would be a self-reflective character - without dwelling for too long. We don't need an angst-y Doctor, but just enough introspection to give him some fully-fleshed fallibility.
My Doctor would also be capable of great kindness and generosity. He'd be a fully fledged interventionist when the moral case was overwhelming for it. His 'meddling' would also have some unintended consequences - either local or in the wider cosmos. Sometimes he would plug one leak, only to cause others down the line.
He's wouldn't be the type of Doctor to hang around for victory parades; he would slip off quietly back to the TARDIS just to avoid being lauded.
2) What sort of companion(s) would you cast? What character dynamic would you aim to create?One female companion. Indubitably beautiful with a cracking arse.
She'd have the human touch; a contra-point to the sometimes alienness of the Doctor; a moral checkpoint for when the Doctor becomes too rational to see the emotional and social impacts of his interventions. She would also provide occasional common sense solutions, like a human Occam's razor when the Doctor is overthinking a situation.
She'd be warm, tactile, and display openness to new experiences. Not with gushingly stupid enthusiasm, but intrigue, curiosity and a stout heart.
3) What format would the show take? Serials? Single episodes? A mixture of both?A selection of 45 minute, mainly 2 parters, but with the occassional self-contained story. I don't think you can get away from the realities of modern TV with this one. Plus, the 25 minute thing just means a bunch of stupid cliffhangers to write into fluid action and drama. One cliffhanger per story is fine, but you don't want to get to the stage where the Doctor repeatedly goes wide-eyed and says 'look!' (cue cliffhanger scream).
4) What sort of tone would you aim for? Would you emphasise gothic horror, hard sci-fi, comedy...?I wouldn't entrench the show in one style. Tone is a little different. The show would take itself seriously again. There would be little in the way of self-referential humour, datable cultural references or intertextuality.
Canon references would be kept to a minimum in order to give the show a fresher feel. The show would feel like a proper drama again instead of a melodrama. It would be the sort of eye-glue that grips kids and parents alike, without teetering on the bridge of becoming bathetic.
Humour would be saved for the opening scenes and denouements, so as not to despoil serious moments. I'd avoid the use of bodily function/sex jokes, or scenes that amounted to extravasate gurning. Sharp one-liners, mild-teasing, and the sarcastic shooting down of obviously stupid people or ideas would be the order of the day.
5) Would you be keen to bring back classic villains or would you rather focus on creating new ones?I'd avoid classic villains for the first season, or do a big reveal at the end of it. The latter would tie into the series meta-narrative.
I'd completely avoid bringing back obscure fan favourites. No Chumblies or Quarks in my Who!
Any returning villain would need their sense of threat re-established. The Doctor would refrain from casually mocking his enemies and make the audience believe they were a threat. The jeopardy would be dialled up to 11, and the resolutions would be bold enough to match the threats. No big red buttons or resets. Consequences, always consequences. Bad or good.
Depending on production costs, it would also be nice to get away from the Trek-like humanoid iterations of monsters. My baddies would take new forms based-upon the environments they evolved in and evince new forms of communication other than telepathy and/or speech.
6) What sort of incidental music would you use?Probably a return to minimalistic, creepy soundtracks and absolutely NO FUCKING BRASS WHATSOEVER. I'd like to see competent, highly creative musicians brought in, like Hildur Guðnadóttir of Joker (film) and Chernobyl fame. Maybe even reform the radiophonic workshop and give air to something experimental once in a while.
7) What would your TARDIS interior look like?Probably like a larger version of the secondary console room. The scanner would return, as would the internal doors. Lighting would be warm. The overall feel would be night-time hygge; warm, ancient, and yet replete with technology. There'd probably be loads of opened books, half-completed projects and a mouldy cup of Vagorian beverage on the edge of the console too.
Are there any aspects of NuWho you'd choose to retain?The 45 minute format. Maybe the Dalek design, but in gunmetal or other known, classic Dalek liveries.
9) Any other comments you may have.My theme would be an authentic homage to the original theme, keeping many of the original sounds. The titles would be zero CGI. Someone would have to come up with some proper never-seen-before practical, creative effects.