@doni49 Your first suggestion is a separate idea (the 2nd IS the same), however, I'd actually prefer that it was implemented (being able to hide a parameter from the user in the project) instead of this one. I actually don't mind creating a bunch of "Show..." parameters because then I can see the logic (the formula is visible in the Family Types dialog), which makes it fairly easy to manage. If that same calculation was buried in a separate dialog attached to the Visibility checkbox, it could get cumbersome to check (AND to update).
So in summary, even though I also wanted it when I first started making my own families, I vote AGAINST this idea, and FOR being able to hide parameters (so we can see & manage the formulas in the Family Types dialog, but be able to hide them from users for a cleaner interface).