But I would give up all of these for an interactive debugger. The series below shows how Common Lisp debuggers are light years ahead of the Clojure.
http://malisper.me/2015/07/07/debugging-lisp-part-1-recompil...
http://malisper.me/2015/07/14/debugging-lisp-part-2-inspecti...
http://malisper.me/2015/07/22/debugging-lisp-part-3-redefini...
And this is important. I develop Clojure for a day job and this is a constant PITA.
Rich Hickey discusses reader macros here: http://clojure-log.n01se.net/date/2008-11-06.html
Quotes:
"Clojure doesn't allow user-defined reader macros because they can't be combined - there's no namespace support, unlike for regular macros"
"CL has user reader macros and the consensus is to avoid them"
"you are unlikely to convince me they are a good idea"
"I recognize fully this is less flexible than CL in this area, OTOH, I'd like to think Clojure will engender less desert-island programming than did CL -- speaking a common language fosters library development, shared idioms etc. When everyone creates their own language there's less of that"
"and even standard reader macros pose an understanding challenge for newcomers"
Compilation units are discussed here:
http://batsov.com/articles/2015/06/16/cider-0-dot-9/
Bozhidar Batsov just recently did a podcast with Cognitect where they speak about this and other things related to Slime and the Clojure programming environment: