V1/V2-without-any-V3/V4-update -to-be-updated (+hopin if SONiKa gets one, she gets her glitches gone and recorded on a better mic)
A crispy, womanly female voice
A "smoky" (aka breathy yet firm and not too raspy) mature male vocal
French, Italian, Portuguese, Vietnamese
A childish female Engloid vocal (kinda like Yuki.... Though AH-Software wanted to make english banks using Native sharing same voicetypes, so this one may not be that urging)
A voice à la Kim Wilde for a female Engloid
A voice à la Phil Collins for a male Engloid
Meaw coming back with Japanese+Thai (though impossible)
Anri coming back, even if she stays private, with voiceroid+vocaloid using her two voicers' voices (though impossible too)
A second Mermaid Melody voicer (yep, Seira's voicer voiced CUL hence why i say "a second" ), preferably Mayumi Asano (Rina's voicer)
Maybe a Love Live! one, but as I barely know it, I don't know exactly who could have quite an unique voice to try it out...
Kyoko ... Wait no, even much more impossible than Meaw+Anri's coming-back, even Ring would have much more chances of coming back, than her to be turne into a Vocaloid
REV to get a Vocaloid voicebank (so CUL coud have her companion for always)
Discoish vocal?
Male vocal from i-Style (not sure about whether teenage, shouta or adult)
CV-04 x CV-4CB PLEASE CRYPTON
Galaco English, though not urging (plus with her three VBS -2 singing 1 talking- are enough atm)
Azuki and Matcha coming back (though impossible as well)
... ok I ask too much, don't I ? ='D Though I forgot half of what I was saying