Provisional solution, that is.

$ rename -v "\$_=lc;s/&/ and /g;y/()'/--/sd;s/(?:(\.)|(-)|[\W_])+/\$1|
+|\$2||'_'/ge"  *
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Shell quoting is nasty. The unprotected perl expression is:

$_=lc;s/&/ and /g;y/()'/--/sd;s/(?:(\.)|(-)|[\W_])+/$1||$2||'_'/ge;
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I took the '&' handling from here and parv's preferences for '.' then '-' then '_' when grouping but with my own (re)implementation. My test data was pretty minimal and I'd welcome improvements or even better test cases.

Brad

my @f = (
    'Godspeed - Sunshine and Gasoline.mp3',
    'Pogues - Token Celtic Drinking Song.mp3',
    'The Pogues - Beer, Beer, Beer (Irish drinking song).mp3',
    'Hell\'s Ditch',
    'One&Two.mp3',
    'A!!  ...--B._._.C_-___-_D-._.-E',
);
                                                                      
+                          
for (@f) {
    print;
    $_=lc;s/&/ and /g;y/()'/--/sd;
    print;
    s/(?:(\.)|(-)|[\W_])+/$1||$2||'_'/ge;
    print;
}
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Here's how I use it in the 'clean_name' script

#!/usr/bin/env perl

# I couldn't work out how to escape this for a shell alias
my $cmd = join '', split /\n/, <<'CMDS';
$_=lc;s/&/ and /g;
y/()'/--/sd;
s/(?:(\.)|(-)|[\W_])+/$1||$2||'_'/ge;
s/^[._-]//; s/[._-]$//;
CMDS

system('rename','-v',$cmd, @ARGV);
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