1) Easier to learn and remember syntax for polyglots. No more Googling, shit like "what was the syntax for try-with-resources or the new multi-catch feature in java"?
2) The language tooling is so much easier to get right. The parser for Ruby is 10k lines. What the actual fuck? How can you expect people to make good tools if they can't get past the parse step?
3) Macros!
4) No fucking precedence rules. I don't want to memorize that the precedence for 'and' and && is different in Ruby and how 'and' interacts with the precedence of other operators like assignment.
5) Structural editing.
I might have forgotten a few, but 2) and 3) alone are killer features.