Terri Hawkes for Sailor Moon
The original Darien: Rino Romano for Darien
Just the original cast over all, even if it was the original Serena, that would be fine. Just ugh. xD

Oh man
I'm totally going to have to think about this.

VIC MIGNOGNA AS TUXEDO MASK!!! And CAITLIN GLASS AS SAILOR MOON

I'm more familiar with English voice actors than Japanese, so I'm gonna share who I think would be a good fit in the english dub, should there be one (and have the role I know them from in parenthesis):
Sailor Moon: Hilary Haag. (Maria Osawa in Canaan)
Sailor Mercury: The only person I can think of for her is Karen Bernstein, but she's retired, so... :/
Sailor Mars: Michelle Ruff. (Chikane in Kannazuki no Miko, Rita in Tales of Vesperia)
Sailor Jupiter: Brina Palencia. (Juliet in Romeo x Juliet)
Sailor Venus: Carrie Savage. (Madoka's mother in Madoka Magica)
Sailor ChibiMoon: Christine Marie Cabanos. (Madoka Kaname in Puella Magi Madoka Magica)
Sailor Uranus: Gwendoline Yeo. (Domino in Wolverine and the X-Men)
Sailor Neptune: Colleen Clinkenbeard (Cordelia in Romeo x Juliet)
Sailor Pluto: Ali Hillis. (Emma Frost in the X-Men anime)
Sailor Saturn: Wendee Lee. (Umi Ryuuzaki in Magic Knight Rayearth)

Yeahh, I've actually been thinking about this since the anime was first announced.

Dub: I pretty much would love all the Inner Senshi to be voiced by their end of classic/start of R voice actors.

But Rei, MAN, I need Katie Griffon. LOVED her as Raye. *-*

I would love it if Aya Hisakawa and Michie Tomizawa came back to voice their roles (Ami and Rei, respectively).
Mostly Aya, though, I love her voice. <3

A part of me hopes that if Ryoko Shintani (She voiced Hitomi from Madoka Magica) auditions for a part, she can voice one of the senshi, and not a minor character or something. Honestly, from her voices that I've heard so far (Madoka Magica and Pani Poni Dash!) I can only really see her voicing a younger character. Like PallaPalla/Sailor Pallas or maybe Hotaru.

As for English actors, I haven't really thought too much about it. Although I wouldn't mind if Emilie Barlow came back to voice Minako. I like Katie Griffin as Rei, too; She's so adorable. *Has episode 90/83 in mind*

In the dub:

Sailor Moon- Terri Hawkes
Sailor Chibi Moon- Stephanie Beard
Sailor Mercury- Karen Bernstein
Sailor Mars- Katie Griffin
Sailor Jupiter- Susan Roman
Sailor Venus- Emilie Barlow
Tuxedo Mask- Vince Corazza
Sailor Uranus- Sarah LaFleur
Sailor Neptune- Barbara Radecki
Sailor Pluto- Sabrina Grdevich
Sailor Saturn- Jen Gould