Well if we're going for Kaori and Haruka...
https://www.youtube.com/watch?v=5RjANzl5l74
young-ish Kaori foreba
This is nice.
Oh yeah!
That pointed (rather than light or breathy) head voice at 1:16 is a power Kaori rarely uses, sadly. I always like when she gets to do a head voice duet harmony with Yuriko or Joelle. It's one strong point she has, but doesn't get to use as well.
She can go breathy falsetto, light head voice, connected head voice, and belt to quite a high pitch level. It's part of the reason she's so versatile.
Her kryptonite is essentially the kinds of songs she gets written for her; that's where she gets failed most of the time. That and the fact that she from time to time goes slightly off-pitch in a live setting and doesn't seem to realize it.
I don't know what her view is of her own career and how she wants to be seen as an artist. In my view, she always shines in Haruka's fantasy compositions, such as this song, and also with Sound Horizon, as well as (I would say to a slightly lesser degree, shock!) Kajiura's (only because Kajiura doesn't give her the focused solo vocal writing as much that would make her shine, in my opinion). Basically she needs interesting melodies to sing in a solo context.
Kajiura utilizes her often as a mirror to the main lead soprano (previously Wakana, now Joelle), so she sings the verse 2 (or comes in out of the blue in a supposedly solo song as you've been complaining about) to give a contrasting voice to the first lead vocal. You might not get Kaori leading a series of songs with strong lead in a row, apart from maybe YKL16?