My first thoughts:
Dracula: Viggo Mortensen
Mina: Anne Hathaway
Jonathan Harker: Eddie Redmayne
Van Helsing: Liam Cunningham
Jack Seward: James McAvoy
Lucy: Joséphine de La Baume
Arthur: Matthew Goode
Quincy: Matthew Fox
Renfield: Michael Sheen
yours?
Dracula- Collin Farrel
Jonathan Harker- James McAvoy
Mina Harker- Eva Green or Oona Chaplin
Van Helsing- Gary Oldman ;) or Liam Neeson
Lucy- Rebecca Ferguson
Steward- Domhnall Gleeson / Mads Mikkelsen
Arthur- Tom Hardy
Quincy- Ben Foster or Chris Pine
Renfield- Ralph Fiennes, Paul Giamatti, or Tom Waits(If you've seen Seven Psychopaths then you know he still plays a good crazy person)
My 2018 cast :)
Dracula: Tom Hardy
Mina: Elle Fanning
Jonathan Harker: Logan Lerman
Van Helsing: Jason Isaacs
Jack Seward: Daniel Radcliffe
Lucy: Anya Taylor-Joy
Arthur: Aaron Taylor-Johnson
Quincy: Liam Hemsworth
Renfield: Steve Buscemi
Dracula: Michael Fassbender
Mina: Alicia Vikander
Jonathan Harker: Tom Hiddleston
Van Helsing: Ian McKellen
Jack Seward: David Tennant
Lucy: Alice Eve
Arthur: Benedict Cumberbatch
Quincy: Chris Evans
Renfield: Hugh Laurie
Dracula: Adam Driver
Mina: Rebecca Hall
Jonathan Harker: Dan Stevens
Van Helsing: Charles Dance
Jack Seward: Daniel Radcliffe
Lucy: Sarah Gadon
Arthur: Domnhall Gleason
Quincy: Alden Ehrenreich
Renfield: Michael Shannon
2020 cast
Dracula - Keanu Reeves
Mina - Emilia Clarke
Jonathan Harker - Tom Hiddleston
Van Helsing - Peter Capaldi
Jack Seward - Daniel Radcliffe
Lucy - Vanessa kirby
Arthur - Timothee Chalmet
Quincy - Chris Pine
Renfield - James Mcavoy
Dracula: Michael Fassbender
Mina: Ana de Armas
Jonathan Harker: Jamie Bell
Van Helsing: Kenneth Branagh
Jack Seward: George MacKay
Lucy: Imogen Poots
Arthur: Richard Madden
Quincy: Armie Hammer
Renfield: Matt Smith