Plugin support is a real challenge... anyway we are seriously building a white list of compatible plugins, and so far they are about 90% of the total. For the remaining 10% it is usually always possible to replace them with some external service (facebook-comments or disqus for comments, our Zapier app for mailchimp/drive/dropbox integration, beds24 as booking system, etc)
We also thought about something like your idea (keep a second installation live somewhere to submit the data), but, as you will have to host your real WP somewhere, you will lose one of the main benefits of HardyPress, namely to have your site unbreakable.
Plugin support is a real challenge... anyway we are seriously building a white list of compatible plugins, and so far they are about 90% of the total. For the remaining 10% it is usually always possible to replace them with some external service (facebook-comments or disqus for comments, our Zapier app for mailchimp/drive/dropbox integration, beds24 as booking system, etc)
We also thought about something like your idea (keep a second installation live somewhere to submit the data), but, as you will have to host your real WP somewhere, you will lose one of the main benefits of HardyPress, namely to have your site unbreakable.