Automatching parens (parenedit?), rainbow parens if you want, a built in repl, and after your repl is started for the namespace you are currently editing, auto suggest for any namespace in dependency graph. Viewing any included namespace code is simple as a double click - very helpful for learning clojure. Edit the file and after a key combo, your repl has your new function definition.
Counterclockwises workflow is pretty nice. I like it. I don't even have to go to command line to update deps, just edit project file and right click update dependencies. The only thing I use the command line for currently is lein ring server.
Eclipse has the concept of templates which you can define for other content types, but CC's editor isn't enabled to use them. I sort of missed them at first, but didn't after I realized anything I would put into a template should probably be a macro in clojure.