Awesome plugin.
One request ... can you provide a mechanism for setting some of the optional parameters for the API's send method?
Specifically, I need to set preserve_recipients to false, in order to hide the full recipient list in the delivered email.
What would be nice would be the ability to both:
1) specify optional params in the global plugin settings, maybe as a simple JSON string like {"preserve_recipient":false, "tags":["some extra tags"]}, formatted as per the API spec.
2) provide them programmatically at run time, probably through $input->set() and get(). So as an extension author, I can do a $input->set('mandrill_send_options', '{"preserve_recipients":true,"tags":"foo bar"}') before I call J!'s mail API to send my mail.
-- hugh