[pirateking]

I can vaguely imagine a more advanced numeral system based on geometric visualizations in 2 or 3 dimensions (rather than the existing 1-dimensional digit string), that is also more suited to probabilistic representations than fractions or decimals.

Relational reasoning is a key use case to be considered for any popular numeral system (How many do I have? How do I signal that amount to others? Do I have more or less?). For small, whole quantities (<100), alternate numeral systems could likely reach a similar learning curve as Arabic numerals. Very large and complex quantities, and things of a number theoretic nature are probably areas where a future numeral system will be differentiated.