While I have heard nothing new since last August, myself, I can repeat what I heard then, which is there'll be plenty of room for cameos, for FanService at the very least, and of course Vimes could easily be the "seen once or twice every episode" type of character. (It's a pity Pete Postlethwaite isn't available, being Author's Choice.) Going along the Casts Of Unknowns route might be best, though. (Saves the arguments over whether Stephen Briggs or Charles Dance or Jeremy Irons gets to play Vetinari... Or, indeed, Rob Brydon, as his voice only, once more.
)
Avoid David Jason. (The joke, prior to Going Postal's release, was that he was going to play Moist in that, as
well as Rincewind in the TCOM/TLF mash-up and Albert in Hogfather. I don't doubt his talent, and I like his stuff in general, but... no more, please, except for maybe any direct sequels/prequels of his other works for continuity's sake.)
As already mentioned, the picture in the OP (established Kidby 'canon' picture, that one[3]) is basically of Carrot's... umm. second night? First day of full duty. Unware that you
don't go into the Mended Drum and enquire as to whether they're abiding to the "Control Of Liquor And Wines Act, 1221, paragraph 3, subsection 5" (or whatever it was) he found himself in the same sort of situation as Vincent the Invulnerable did when he went in there and announced that he was
called "Vincent The Invulnerable" (verdict: suicide). Except, of course, that this was Carrot. The six-foot dwarf who could (and often does) knock trolls out with a single punch. But (at this point)
nobody knows what Carrot is capable of! (And Carrot, being carrot, actually arrests the head of the Thieves' Guild
for being a thief... How silly is that, eh?
Read "Guards! Guards!" for details. If you haven't, it's a good place to start anyway, in the Discworld canon (but I doubt anyone reading this thread
hasn't at some point been involved in the Discworld canon, so that might not actually apply to anyone here... but read it/get the audio book (unabridged[1] ones, preferably) anyway, if you haven't already.
Somewhere along the line, Carrot has wised-up significantly (he probably has a latent gene for diplomacy, maybe even diplomatic subterfuge, in amongst his other ingrained and dwarf-nurtured leadership qualities... I'm never really sure whether or not the "Throw the book at him!" incident in G!G! was him being innocent or... expedient), but then with Carrot helping bring Vimes and the (Night)Watch back from obscurity, so the Watch and the City also comes to appreciate that Constable (later to be Captain) Carrot
is not a victim, with many an unspoken compromise much along the lines of the Patrician and the UU regarding the payment of taxes.
The sandals point, I'll agree with. Although in my own Watch costume (never worn in any Masquerade, because I'm too basically too shy to go on stage[2]) I've made 'sandals' based on those and similar pictures. I found some
actual sandals with a "newsprint" pattern on the upper part of the sole-piece (this part, at least, matching the written concept of worn boots with paper/cardboard lining), took off the "thong" elements and then used some dye-darkened chamois-leather to construct the upper. Indeed, not very practical if I were in danger of having boots or heavy/sharp/pointy weapons aimed at my feet. Of course, one of the main thing about the Watch, pre-Carrot, is that you
don't get involved, and being light on your feet is often better than having heavy boots.
(Carrot's immediate predecessor, mayherestinpeace, forgot this. Carrot has gotten away with this when he tried the same thing. The worst threat
along those lines in G!G! was soon after the point that picture in the original post was depicting (although they hadn't run into trouble, so much as stumbled and swayed), and they might
well have managed to deal with their attackers as they became insta-sober from shock, but that point becomes moot for the very reason that Vetinari at first wanted the wall involved to be whitewashed. Until he was reminded that it would attract far less attention to just demolish it.)
[1] Not that I dislike Tony Robinson's readings of the books, but the Nigel Planer/Cecilia Imrie/Stephen Briggs audio books (ISIS Audio) are the full monty.
[2] As an off-topic example, when I was at secondary school I auditioned to be the gorilla (!) in a pantomime. Forget
which pantomime, now but it wasn't a
traditional part of the pantomime (
might have been Jack And The Beanstalk), so that detail doesn't really matter. I thought I'd try that because I would be totally encased in costume, there'd be very little in the way of line-learning to be had, and I thought I had the movements down pat. I failed the audition (I may have been more chimpanzee than gorilla, in hindsight) and the girl who actually got the part seemed to do a lot better than I think I would ever have done. But (not in any school production, but elsewhere) I've been involved in behind-the-scenes AV setups, and done a fairly decent amateur job of it, if I say so myself. Have often been tempted to go into some Stage Crew position, except that my big thing is of course all-things-IT...
[3] He tended to make Vimes either Clint Eastwood or Pete Postlethwaite, whenever he resembled anyone Roundworld that I could recognise. Probably the latter after PTerry had expressed his own ideas about the character, but the Author has always been happy with artistic licence, so I don't think there was any compulsion there. He's generally gravitated towards the look most recently seen on the cover of
Snuff, which still has some Dirty Harry to it, but not entirely so.