You’re definitely looking onto the right plugin. It allows you to add so called “global snippets”. That means that you can add snippets for specific posts, post types, categories or whatever you need and add them dynamically depending on your rules.
Sounds complex? Here is an example.
The plugin comes with a pre-installed globally active “Article” snippet. This is because most users are using their WordPress site as a blogging platform and every post should then be marked as an “Article” (Google has a nice explanation on what it does here).
So for that I set up a global active article snippet and adjusted it so that the generated snippet-code is only distributed when the current post type is equal to “post”.
The snippet itself uses parameters from that post like the post title, the post content, the date and many more. So you don’t need to include this data manually by yourself.
Sound’s good? Yes, it is. It should save you a ton of work.
But there is more! Some customers currently using the plugin for creating recipe snippets. For this they set up a global Recipe snippet and activate them on some categories only.
Of course, making donuts is not the same as preparing a Thai creen curry. So they mark some of the properties, like the ingredients-property, as overridable. And with that the plugin allows them to overwrite those parameters directly in each post.
To make it short: you can define a parameter globally but you can also overwrite it in each post. Up to you!
What the plugin cannot do for you.
Although the plugin allows you to built nearly every snippet you want and goes way beyond what other Rich Snippet Plugins are doing, there are some limitation.
Let’s say you’re using the Advanced Custom Fields plugin. A plugin that allows you to generate custom fields on some of your custom post types. Such plugins may save data into the database that the Rich Snippets WordPress Plugin cannot read. So this would require work on your site together with your own developer.
This may also be the same with data from third party themes.
However the plugin makes extensive usage of WordPress’ hook-system. That means that it’s possible to extend the plugin without touching its core code (so that you can still update it). If there is a filter and/or an action hook missing, please let me know and I’m sure we can find a solution that fits.