So first off, I want to say that I greatly respect the work the team is putting into this, and regardless, I'm looking forward to it when it gets completed.
That being said, I have a differing opinion, with heavy emphasis on the word opinion, on the decision to use Yuki rather than Yukino. Since this translation is going to be bringing Eternal Punishment in line with the rereleased translations of Persona 1 and Innocent Sin, it seems disjointing. As far as I remember, Yuki is used nowhere in Persona 1 or Innocent Sin, as the only three characters of P1 listed with a nickname in the manual are Mark, Brown, and Elly, with the opening scene listing Yukino's nickname as... Yukino in her introduction, which isn't surprising since most of the cast doesn't have an actual nickname. I'm pretty sure Innocent Sin is similar, but I'm a little foggy on it since it's been a while and I've been waiting for a translation of Eternal Punishment PSP to play it again. Either way, she's described as being fairly well respected and a bit of a no-nonsense type of person, meaning she probably isn't the type of person to go by a nickname. I mean, yeah, there are exceptions, but if she hasn't used one in the previous two games, she probably wouldn't use one now. It'd be like if Kei suddenly started to go by Nate, which as far as canon goes, he never has. And he has a similar no-nonsense attitude to Yukino.
I get that Yuki is personal preference for the translating team, and I respect that. I'll still play the translation when the patch comes out. I'm really looking forward to it. It's just, I felt it was worth pointing out.
That, and Yuki just leaves a poor taste in my mouth as a reminder of what originally happened to P1.