A.
I’d like to have the ability to display the result of a formula onto a form, just like it does when I’m in the Grid view, without needing to add extensions.
Use case :
My form is some version of a shopping list , the user filling the form can see the total on the screen

B.
An alternate approach would be the ability to assign Numerical values to a Text string and then, give me the function to just add values chosen in a field or fields and then display the result on the form, as explained above.
(so I don’t have to figure out the formula!)

But if A were the easier option of the two, please consider it!