Question: Is it possible to supress the parenthesis in the output of the Empty Symbol or how to get a printed one that Maple knows how to remove

Here is the layout challenge: Whenever the value of a physical quantity is one as in

mass = 1* Unit('kg')

automatic simplification removes the one and the output displays

Desired would be which reads better (in particular when used inline in text passages).

Using the Empty Symbol

mass = ``(1)*Unit('kg')

an expression with parenthesis is obtained (that can be removed in subsequent calculations with the expand command) which looks worse than my current workaround of using floats

(Introducing floats in expressions is not always acceptable)
So the idea would be to use the empty symbol for initial parameter definition in textbook style layout and remove it with expand in subsequent calculations.

Any other symbol that prints as "1" that can be removed in later calculations by Maple commands is welcome as well. It should be better than

mass=`#mrow(mo("1"));`*Unit('kg');
subs(`#mrow(mo("1"));` = 1, %);