To clarify: my comment was about my experiment with having tables print with "{a 1 b 2}":
arc> (list (obj a 1 b 2))
({b 2 a 1})
it was this that I found hard to match key value pairs in a long table output and the curly brackets weren't standing out enough by themselves for me when I was scanning a large amount of debugging output.
For input, when I'm the one doing the typing :) -- and anyway the number of key value pairs is usually small anyway -- I'm all for typing fewer parentheses ^_^