Hi! I moved your comment to a separate thread, because that's a better fit 
And yes, this is a nice idea and I already had this in mind. So we'll definitely be adding this in the future!
This is a bit more difficult and introduces the problem of how matches vs. predictions should be handled, and which to prefer in case there are overlaps. For NER uses cases, you could default to showing either the prediction or pattern match if they disagree – although, it's often useful to see both, but you still want to make sure that your final data ends up with only one version. And while the span categorizer can predict overlapping spans, you'd often still want to pick one span that's most consistent. For instance, the model may predict a "the" + noun phrase, while your pattern describes only the noun phrase. In that case, you want to make sure that your final data only ends up with one of them, not both. The "comparing annotations" workflow described in this issue goes in a similar direction, and it's definitely something you could implement in a custom recipe: Recipe for comparing NER model and manual annotation - #3 by haishao