It would be nice if you could use create test conditions that look at adjacent features within the tester/test filter instead of having to use the attribute creator followed by a tester
I was looking for a conditional feature creator when I stumbled upon this idea. Somewhat similar except that I wanted to add a feature in a data stream when that data stream has one or more features. If no features arrive at this conditional feature creator, the data stream stops. If there is a feature, a new feature is added to the stream.
Maybe a null feature manager idea would also work for me.