FWIW, Mathematica is one language I know that allows omitting the multiplication sign—two primary expressions (in ES terms) side-by-side is always a multiplication.

Yeah, dumb of me not to notice that, but u know what? That's actually rather nice as it shuts the door to many confusing variations of the syntax. If we only allow for a number multiplier (on the left) and a multiplicand restricted to a numeric variable identifier, there would be zero ambiguity and it will be more than enough for most cases. This means we can still do stuff like 2Math.PI and 2 / 3x. Personally, I think it's best suited for those cases too. Bcuz, something like aDozenmangoes looks awful compared to aDozen * mangoes but 12 * mangoes is way awful than just 12mangoes. Get what I mean?