For reference, an S-expression based syntax that could be used for this example: (todo "housework" (item :priority high "Clean the house.") (it

For reference, an S-expression based syntax that could be used for this example: (todo "housework" (item :priority high "Clean the house.") (item :priority medium "Wash the dishes.") (item :priority medium "Buy more soap")) Your syntax certainly has advantages, but one can easily prefer S-expressions in this case without appealing to vague values like "aesthetic purity," nor are there any blatantly obvious "practical" downsides to using a more fully parenthesized syntax.