If they removed the murder plot (or you know addressed it in the first 70+ hour game ) I'd almost say zero could make for a decent stand alone title. I didn't play sky trilogy (started with cold steel 1 an 2) and didn't feel like I was missing out on too much. But I get it that isn't their operating procedure and they have to make money off them engines. It's just a shame though.
I will give them props that despite zero being 13? years old it's not super dated feeling. And I played the ps4 version which doesn't have the added enhancements the switch version got. I will admit that having a chat log would be nice though especially when the game just randomly advances/skips text boxes and voiced scenes for no reason.
Party wise it felt like the game focused only on tio with randy getting some mentions on stuff here and there and ellie just existing to be upset every time lloyds harem fusses over him. Ellie could have gotten more screen time and had at least some basis for it due to her grandfathers stuff with the government but for whatever reason they couldn't be bothered to do anything with her character.
Funny enough Wald could have easily been a party member given how much screen time he was getting. He certainly had more stake in the plot than the others given that outside Noelle he's the only other person that is born and raised in crossbell. Lloyd and Ellie lived outside of crossbell so they don't really count as much to me.