You ask about redirecting STDOUT and STDERR for system calls given as lists. A good way to do this is with the module IPC::Run.

use IPC::Run qw( run ) ;
run \@cmd, \$in, \$out, \$err;
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One idea you might be able to use for parameterizing your error messages for various commands would be to pass in a hash reference containing explanatory messages indexed by return codes. Also see perlvar for how you can use the variable $! to obtain error message strings after a failed system call.

Finally, the reason spelled-out file handles are considered "bad style" compared to IO::File is that they create global names, which might conflict with other modules. IO::File uses unique private symbols instead.