Variant (Untyped) parameter for function/procedure

Dear Members!

As I experienced, the functions/procedures extremely depend on parameters
(very typed).
So if I have to restructure the input parameters, I can't modify the
function, because I have to recreate the dependents too.
For example:
I have a type. If I pass this type to a function, I can't change the
structure of the type without dropping and recreating the function.

create type blahtype as (a int, b bool);
create function blahcheck (input blahtype) ...

If I have many dependent functions this causes that I have to drop
(recreate) everything - just for an extra parameter. And sometimes this
extra parameter doesn't change 10 functions, only one. But I have to
recreate them all (without changing the body).

Is there any way to use a Variant parameter?
Like this:

create procedure test(IN Input Record, OUT Output Record)
...
Time = Input.Time::timestamp;
...

Output = SomeHowMakeItTyped;

Output.Result = 1;

...

Caller:

...
for r_in as select id, name from blah into
...
test(r_in, r_out);
if r_out.result <> 0 then ...

Or:

create procedure test(IN Inputs Records, OUT Output Record)
...
for Input in Inputs:
Time = Input.Time::timestamp;
...
Output.Result = 1;
...

Or is it impossible, because of the PGSQL's philosophy (very typed)?

If it is not possible then I have one way I think.
It is a JSON data type for inputs and outputs.

Is that right?

Thanks for your any help, info!

Best regards
dd