[dfox]

Common name for what you call "universal numeric type" is "number tower". Most lisp dialects have something like that. What that means is that you have classes for small integers (fixnum), arbitrary precision integers (bignum), fractions, floats, and even complex numbers along with the appropriate abstract base classes (eg. integer, rational, real...) and arithmetic operations transparently use the most appropriate type for the result, i.e. the result of "1 / 10" comes out as "1/10" (of type fraction) and not as float "0.500...something".

Python 3 has mostly same approach to number types.