Why do you think there is no such person amongst the UI team already?
And why do you think all that you mention, that is just a normal way to approach a new project analisys in any team, has not already been done?
And once and for all, why do you keep repeating:
When it has been said here many times that:
1.- It’s already a core value
2.- It has been worked and it’s contunuously worked in the UI team
And finally:
Do you value something the UI team that it’s present right now in the Core dev team?
Because for your words it seems that you don’t value them, their experience and their work at all, and you talk as if they were not part of the team and if they were not contunuously working and fighting for improving things, and I say fighting because sometimes it can be a real fight to reach a high quality result to the complex problems they face everyday.
UI/UX have room for improvement in Blender in many ways, from many points of view, but I don’t think trashing all the work that has been done and it’s being done already is a good way to focus on it.
I myself don’t agree with several decisions made, as some others, but that does not mean that the UI team, as the rest of the team, is not working hard and putting a lot of effort, or that they don’t know what they are doing, if there is some idea to improve UI/UX right now, great, but we have a great team working on it, so instead of trying to bring a new person that may or may not know what Blender is all about, specially if it’s a volunteer, because in such an important position a volunteer could decide to stop working at any time, it’s better if some good proposals, documents and ideas are properly presented to the current team IMHO, we have a great value in house, and often this gets over-watched.