Gumi:
Verdict: NO / Reason: VOCAL NOVELTY
Sadly I predict it's over for Gumi. Praised during Vocaloid2 for sounding more natural and realistic than her competitors, the features that originally made her stand out now plonk her solidly in the most competitive category of natural, flexible contemporary feminine voices. Despite her nailing EASE OF USE with a SynthV update, the decision not to capture Megumi's full range of expressiveness puts her at a disadvantage against SynthV's many other Nice Realistic Singer offerings. This leaves the Green Character space dangerously vacant (now's your chance, Ryuto
)
Kaito:
Verdict: NO...but potentially YES / Reason: EASE OF USE
Very simple: any old voicebank that hasn't had a recent update is much harder to use than modern vocal synths. However, Kaito has the advantage of being one of our few iconic male characters, and I think Naoto Fuga could pull off a unique vocal performance on a variety of modern engines: if updated, I foresee a potential future for Kaito with the popular kids.
Gackpo:
Verdict: NO / Reason: EASE OF USE
Same as before on the update front, combined with extra hurdles of Gackt's one thousand million crimes, and a design that's more annoying to draw. Under different circumstances, his voice could be quite spectacular, but I don't think that's enough in the modern era.
Meiko:
Verdict: NO / Reason: EASE OF USE, ICONIC HAIR
Ironically Meiko's voicetype is very unique and has been popular when given to other characters, proving she unfairly suffers from a permanent Normal Brown Hair debuff. Luckily she'll always get the Piapro Character bump, so us Meiko fans will stay fed.
Luka:
Verdict: NO / Reason: EASE OF USE, VOCAL NOVELTY
As well as being extremely difficult to use right now (compared to other options), Luka's soft-feminine vocal category has become very saturated. Tragically, this means that soft voices
are popular, and Luka could have potentially surfed that trend to success had she a timely update. Her advantage as a bilingual vocalist has also been thoroughly lost thanks to cross-lingual synthesis. In Luka's absence, producers have been driven to seek out other options. I fear she's lost her niche to newer characters.
IA:
Verdict: NO / Reason: VOCAL NOVELTY
I think IA could still be moderately popular if she had an update that perfectly captured Lia's voice, but having already had some good updates and still losing ground, it looks like Lia's not quite enough to grab people in the era of many polished, realistic voices. She could go the Mai/Ayame route and find commercial success with professional musicians in the anime industry.
Flower:
Verdict: YES...with a few caveats
Flower just needs a voicebank for a slightly newer engine with a slightly more cohesive design and she's golden. Her abrasive voice is very unique, her androgynous/goth vibe stands out visually. cFlower unfortunately nerfed these elements - perhaps a V6 could get her back on track? I believe there is both a gap, and demand, for an alternative rocker girl in the vocal synth fandom.
Other random popularity analyses:
Anri: Has vocal novelty and ease of use, does not have iconic hair
Yukari: Has iconic hair, does not have vocal novelty, ease of use okay but locked to JP only
Kafu: Has iconic hair, has vocal novelty, falling behind on ease of use
Rana: Has iconic hair, has vocal novelty, lacks ease of use
Miki: Has ease of use, lost vocal novelty, red is now taken (dang)
Eleanor: Has iconic hair, lacks ease of use (ease of buying, specifically), vocal novelty had potential. I theorise she could have been the 'white one' under different circumstances.
Yi Xi: Had vocal novelty, had ease of use, achieved popularity once given iconic hair (let's go Vimalion!)
