There's nothing in your settings that stands out to me. Just to be sure, though, I think you should try doing the same print in Cura with Ultimaker's defaults. If that doesn't work then I would try increasing your extruder temperature in 5 degree increments. I've noticed that Ultimakers like to run hotter than most other printers. We have an article coming out soon on the relationship between temperature and speed, so keep an eye out for that. I think it will be helpful to you. Also, have you tried adjusting the tension on the feeder?
General 3D Printing