Counterclockwise has everything you need for a decent Clojure development experience.
The things I find most useful (can't live without!)
- Fully functional REPL
- Paredit mode / automatic paren balencing
- Matched rainbow parens in both REPL and editor
- Syntax highlighting in both REPL and editor
- Integration with Eclipse / Maven for dependency management
- Many keyboard shortcuts (see: https://code.google.com/p/counterclockwise/wiki/EditorKeyBindingsFeatures)
- Perfect for Polyglot projects that mix Java + Clojure
I'm pretty happy overall using Counterclockwise as my primary development environment. Not saying it's better than Emacs, but it certainly isn't lacking anything that is a deal-breaker.