She's losing close 2 set and 3 set matches, often having to break serve to keep even.
I think you bring a vital point here. It is disappointing to see that Nicole, who relies mostly on her feistiness and intense competitive nature to win matches, has such a poor record in deciding sets in her pro career so far (well below .500 and probably one of the worst in the top 200).
Getting blasted off the court by a more powerful ballstriker is one thing, but I would expect her to be able to grind out opponents like Grace Min and Chieh-Yu Hsu (who have no real weapons to hurt her). Yet it's not happening.
How will she fare on clay against the dirtballers who can last for hours? Let's not even think about the grass season.
This is pure speculation, as only Nicole herself could answer this question, but I have to wonder if, deep down, she truly believes that she belongs on the WTA tour.