Predefined meta names and checkboxes

Hi there Tom,

I’ve purchased this plugin for the ability to add product notes in admin orders. Very nice to have this, but there would be some improvements to add:

01. Is it possible for you add another function that will enable predefined meta names? In my case the shop manager has to enter every time a name for the meta, and I would like to have this field already predefined.

02. Also, It would be awesome if in the meta instead of the value field to have checkboxes. In my case, with a restaurant, I want to enable the shop manager to select some ingredients that should not be added to the product preparation. This way, when the order gets into the kitchen, the cook will see what ingredients not to include. If not checkboxes, it can be select with multiple options.

Thanks.