Some of my templates don't require any user input. Others can be configured entirely in the snippet GUI. They don't require any data table input. But in order to run the R Snippet, there has to be input. So what I do is use a Table Creator node to create some random value and use that for the input port. It's not difficult to do, but it makes explaining how to use such templates more complicated. It would be nice if there was an R Snippet node that only had an output port.
Maybe I missed them, but I didn't see any source node for the R Scripting. Not sure how much I would be able to do with them anyhow, as I'm not a Java developer. Or maybe it's easy to implement this sort of thing? 1:2 nodes would also be nice to have (or even better, configurable via a wizard, like for the meta nodes).