Side effect in granting access rights ?

Hello,

I think I have noticed a side effect in granting acces rights (as an admin). I explain here what we observed.

We wanted to have two project leader profiles: one with restrited access, i.e. without financial issues, the other with financial issues. We chose to restrict the visibility to the orginal project leader profile, and created a "Chef de projet Fin." profile. We worked on the various access rights screens, and also with the screen personnalization plug-in.
However, when we disable the acces to the costs for the standard project leader in the "specific accces/ visibility on charges and costs" section, it does affect the "Chef de projet Fin." only for the activity screen (that does not see the costs), but not the project screen. We solved this by granting the right to the standard project leader profile, and hiding it with the screen personnalization plug-in according to the profile. By the way, this plug-in is very powerful.

This  is not a big issue. Since we tested it in our demo/sandbox version, possibly would it be wiser to grant the full rights to the standard project leader profile, and create a "padawan" project leader profile with restricted accesses.

Since we begin in the admnistration, I am afraid we missed something. However, we tried several configurations before reaching our conclusion on a possible side-effect.

We work with version 9.3.5.

Thanks in advance.