This is a global problem -- not just specific to the "open or die" situation you mentioned in your post. If you wish to solve it in a way that makes any calls to die result in a wait period, you may consider overriding CORE::GLOBAL::die. In this case, you would probably want to inject your wait for enter logic into CORE::GLOBAL::die, after dumping $@ to STDERR, and then exit with a non-zero exit status. brian_d_foy has a nice writeup on overriding CORE::GLOBAL::die.

Additionally, if the "print and wait for diamond operator" idiom feels too clunky, you could:

require ExtUtils::MakeMaker;
ExtUtils::MakeMaker::prompt('Please hit enter to exit.', '');
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...which encapsulates the ugliness in prompt, from the core module ExtUtils::MakeMaker. The advantage to using prompt is that it also quietly accepts the "default" (ie, doesn't block) if the script is run in a non-TTY environment.