First: welcome to the Shack! Nice to see other people from Scandinavia on this forum
Please remember to use the scales recommended in the REW guidelines (Up to 105dB if I remember well). Take a llok at the first threads in this section and how other people do it. It will make it easier for everyone to compare your results...
Otherwise, if you want to get a good flat subwoofer response then you should test your sub alone. As far as I can see, your curves are for the two front speakers and the sub, right?
I'm not an expert but I would say that you have a good starting point here. Do you use any form of room correction system?