Thanks for your feedback.
You are saying "The plugin is good as such" - and giving it a 2 star rating? That's confusing and misleading for new users.
Reviews should be based upon what the plugin currently does and as such be rated, not because some features or anything is "missing" currently.
For feature requests and support questions there are better places like the support forum: http://wordpress.org/support/plugin/woocommerce-delivery-notes and/or the "Issues" on GitHub: https://github.com/piffpaffpuff/woocommerce-delivery-notes/issues
To your points:
for 1) Yes, but then you may use another plugin or add that feature via tweak (hook, filter, via a third-party plugin).
for 2) As you say the option is currently there - via CSS. However, this plugin here is meant to be simple and not a "one-in-all" approach.
for 3) This will not happen with this plugin. The PDF feature will be way too complex for such a free plugin and also it justifies not the increasing support load for the developer. Also, PDF features require additional third-party libraries which are all having a few issues (especially in regards of internationalization). --- There are already at least 2 premium invoice extensions for WooCommerce out there and I guess a few more will follow. Also, there is at least one (maybe there are more already?) extension for extended packing lists...
This plugin is a simple solution only - by intention! It will never get certain features that belong in a premium plugin and require also premium support.
Thanks, Dave :)