I would like sqlplus output to be more readable.
Fortunately, you can adjust the pagesize and linesize variables on the fly, e.g.,
foo_owner@FOO> set pagesize 50000 foo_owner@FOO> set linesize 120
You can set pagesize to 0, which is very useful for scripted output, as it will not print any column headers and only print the results. However, if you want to see column-headers but not repeat-them every nth line, set pagesize to something reasonably high.
The linesize defaults to 80, which is fine on a 1980's dumb-terminal, but I prefer this set to a more reasonable width to fit my terminal screen.
You can add both of these lines to your login.sql file (sqlplus will look for login.sql in the current directory or in $SQLPATH environment variable)
-- format output set pagesize 50000 set linesize 120