I think the story was pretty balanced in terms of characters screentime. I was prepared for Honoka and Marie to be involved in the main story, so no disappointment. Also, I don't think TN overlooked the other characters in terms of "screentime". In terms of writing and progression, maybe some characters (those not involved in the main storyline like Eliot, Brad, Lei Fang, Hitomi) are parodies of themselves. It shows, by the way they are placed on the character selection menu, that TN do want them to stay away to the main storyline.
Characters that were definitely robbed are Kasumi, Kokoro, Lei Fang, Hitomi, Brad and Eliot. Nothing has changed for them since... forever.
At least Tina/Bass/Mila/Rig got some new stuff. Having all the cut content would redeem them all.
- Kasumi : maybe there are some scenes with Ayame that were cut
- Kokoro : maybe there are some scenes with Miyako that were cut
- Lei Fang : Lisa & Mila were added to Tina's arc, Lei needs novelty
- Hitomi : should be much more linked to Hayate & the ninja story
- Brad : I was expecting him to look for the legendary salmon, no ?
- Eliot : not much was explained regarding Gen Fu, not even a clue
Another disappointment was Phase 4 : I was expecting her to be reworked to fit her
concept art more, and be her own character. Maybe this will happen in the future, but I loved the "psycho" personality (school girl > weapon of mass destruction). And I think dark silver hair would be nice.