Optional parenthesis and optional separators always force me to pause and parse the code instead of scanning it, because I need to establish the context of every single operation.
I'm sure Carp is interesting, but I would be so unproductive in it.
What do you mean by optional parentheses? Are you referring to the square brackets? Carp is inspired by Clojure, and in both [] is a reader macro that instantiates an array (a vector, as opposed to a list). I'm not a fan of using the array syntax to define function arguments.
I'm not sure what you mean by optional parenthesis. I'd say optional separators are a legacy feature, I don't think anyone writes Carp with separators.
I'm sure Carp is interesting, but I would be so unproductive in it.