Thank you, I'm aware of that.
my question is: if you have a staff of 85, which staff is the most important?
EA
RJ
K
RM
DC tv

Not much between 80 and 90 even. You gain a few points over an entire course

I carried out tests a month or two ago between an EA 80 and 90 on group training sessions lasting around ten days each (for all my players).

Roughly speaking, you gain between 1.1% and 1.5% in relative terms.

For example, if you earn around 60.00%pts per collective training session, that could rise to 60.5%-60.9% in the best case scenario.

Roughly speaking, you will earn between 1 and 1.5 NG maximum in the most optimistic case over 4 seasons of training.

You'll earn even less with individual training. After that, if you have the money, it's always an option. But an EA 80 will do very well.

I think yes, you take on a youngster and keep him for 25 seasons.

Divide 5 million by 25 seasons and it's almost nothing...

A few points here and there is what sometimes makes the difference.
If there's no point in having an EA 90 rather than an 85, why would anyone rather have an 80 than a 75, since the difference will be the same?

Not a very objective answer

Your question doesn't call for an objective answer, but a subjective one. And his answer is very good, because it really depends on what you want from your staff.

If you're training a lot of young players, you'd better have a good assistant to help them make the best progress during collective training sessions, and a good physio to minimise injury time.

If you rely heavily on your youth academy, having a good youth recruiter is probably better than having a weakling.

If every euro is important for your club, the TV channel director (TV channel) and the marketing manager (shop) are also important.

We'll all have different opinions that may be relevant, depending on our own way of playing VF.