What are you using for the Z step height? (Line height)
You could easily do 0.3mm and even 0.4. That makes a huge difference in time. Generally Z height is the single biggest predictor of printing time, even more than speed.
Theoretically you could run that nozzle with a line spacing as wide as 1mm, but you'd have to really drop the Z height, otherwise you'll run into limitations on the total flow rate you can get through the stock hot end.
