I'm gratefull that Funimation is bringing back the old cast for the characters we already know and love. But I do hope that they use their actors for some of the new characters. Helena Taylor was already Zorin in OVA IV, so she should reprise that role in V-VII. But those who never appeared in I-IV should have actors picked for them, and I do have some ideas.
* Christopher R. Sabat as Spirit of the Jackal: Sabat is good at voicing comidec tough guys like Kikuchou and Kuabara, and Jackal Spirit seems to make fun of that.
* Suzy Prue as Heinkel Wolfe: Yeah I know Prue doesn't work for Funimation, but one review of Shamanic Princess critisized her Lena voice for being husky enough to sould a bit masculine. While this killed Lena, I thought, "Hey... that might actually work for Heinkel" since I saw an internet comment saying that his/her seyuu did that too. All Prue needs is to join up with the Hellsing Cast, use a German accent, do some actual fine-tuned acting that shows that she really understands and tries to think like her character, and she's good to go.
* Brina Palancia as Kid Walter: Palancia nailed young boy roles before, and I liked her voice as Ciel Phantomhive in Black Butler, so I thought, "Hey, let's cast her as kid Walter!"
I haven't picked out who should voice Yumie... maybe Monica Rial... Do you have any preferences?
I would love to hear your thoughts!