Thanks for trying Raygun :-)
At present we don't provide an mechanism for non-error logging, but we are working on adding support for it (ideally having something available before year end). We have had people wrap messages in exceptions but, frankly, that's not a good idea and is pretty awkward at best.
Do keep in mind though that you can log custom data with an exception, check out the overloads on the Send methods - you can use custom tags and custom key value pairs. So, if wanting to include just a bit of extra information with your exceptions then this is the place to do it.
I hope that clarifies,