I'll start with Zeki because more people on my timeline know her than my others. Her voice is on the soft side of husky. Warm and low. A little like Shego but without the energy. I narrowed her down to Rachel Weisz in Complete Unknown

A close second was Natalie Portman doing her Jackie Voice but it's a little too high and breathy.

Alexis is on the gravely side of husky and has a lower, more forceful voice than Zeki. It's somewhere betweenvPauley Perrett and Scarlett Johansson but loud and brash and Brooklyn.

.... wow that trailer sounds exactly like how I've been hearing her in my head for YEARS

Maybe a leeeeetle more deadpan? But yeah

Aaahhhhh, gooood! Yeah, but more deadpan, but it's the best I could find. The American accent is an affectation, she's British I think

Darius is hard to pin exactly. He has a rich, warm voice, as deep as he is tall. A bit like Hugh Grant but honestly, the very best voice for him would be the sharpness and enunciation of Jeremy Irons combined with the depth and richness of Alan Rickman.

I dint think I even want to try for Drake, his voice is all over the place. It's high and clear for lots of yelling (Kevin Cronin, Freddy Mercury), but he's also a musician and can affect a soft effervescence (Nate Reuss). But it's always a bight and airy tenor.

Versus Darius' low sitting lyric baritone.

Right, because they did choir together, right?

They did! Drake started very young, in a church choir, and became a Cambridge chorister at around 9 or 10. Darius didn't start singing until college, when Drake convinced him to try for the choir. He already played the viola, so had plenty of musical experience, so why not.