the more subs I import the harder it becomes to keep track of where they are all from

You could import the sub to a different name:

*vlp_func = \&Very::Long::Package::func;
[download]

Update: The following is a means of doing the above with a large number of functions:

use warnings;
use strict;

sub import_func {
   my ($src_name, $dst_name) = @_;

   if (not defined $dst_name) {
      $dst_name = (split(/::/, $src_name))[-1];
   }

   if (index($dst_name, '::') < 0) {
      $dst_name = caller() . '::' . $dst_name;
   }

   my $src_func_ref = do { no strict 'refs'; \&$src_name };
   my $dst_glob_ref = do { no strict 'refs'; \*$dst_name };

   *$dst_glob_ref = $src_func_ref;
}

sub Foo::Bar::func { print("Hello World!\n"); }

import_func('Foo::Bar::func', 'fb_func');

fb_func(); # Calls Foo::Bar::func
[download]

To import multiple functions at once, you can use

import_func("Foo::Bar::$_", "fb_$_")
   foreach qw( func moo bla );
[download]