I've had a few ideas since we played this the last time, so here is, finally, my list of cast choices. I've stolen, I mean borrowed a few I really liked from other people (these are marked with *).
Sisko: Eamonn Walker / backup choice: Lance Reddick*
Kira: Asia Argento* / if you can't get her, backup choices: Christina Cox, Katee Sackhoff**
Odo: John Noble* (PSGarak changed his mind, but I'm sticking to him as Odo rather than Tain)
Jadzia Dax: Tricia Helfer
Miles O'Brien: James Nesbitt
Julian Bashir: Karim Saleh (from BBC docudrama
Hamburg Cell)
Quark: David Patrick Kelly
Jake: Noah Gray-Cabey* (cast a white actress as Jennifer to make this more believable)
Worf: Adewale Akinnuoye-Agbaje
Garak: Robert Knepper* / John Glover***
Dukat: Christopher Meloni
Damar: Dominic Purcell*
Weyoun: Michael Emerson
Female Founder: Mary McDonnell**
Winn: Elizabeth Mitchell (20 years older).
.. wait, can I do this? It's fantasy cast, after all. Oh, you said if it was starting now? OK.
Dianne Wiest
(I'm having flashbacks of Wiest as the Evil Queen in The 10th Kingdom)
Martok: Yaphet Kotto
Rom: Willie Garson
Nog: Frankie Muniz
Ishka: Rhea Perlman
Brunt: Charles Martin Smith
Grand Nagus Zek: Michael J. Pollard
Leeta: Christina Hendricks
* borrowed from PSGarak
**borrowed from Temis the Vorta
*** borrowed from MeanJoePhaser
I've done my homework on short Ferengi-like actors.
I've also recently realized that Christopher Meloni really has to play a Cardassian one day!! During the discussion about
Oz on the TV & Media subforum, and watching
this video, I've been reminded what a loooong, massive neck the guy has!

Not to mention a body that would great in a Cardie uniform!

Then I realized that his two best known roles have been as 1) a devoted family man & authority figure dedicated to his job, and 2) a dangerous, manipulative, charismatic, sociopathic sexual predator/murderer obsessed with making people love him... If that combination doesn't qualify one for playing Dukat, I don't know what does.