Excellent @hansvanoverzee ! Glad to help ;-)
Indeed, flats will help the result a lot. So focus on creating good flats.
Another focus point would be to improve tracking of the object. You’ll notice the noisy stripes in your data. This could be a result of not using a guide camera. So only using the mount to track the object. For each exposure, the object is slightly shifted in one direction (declination drift most strongly) causing the stripes. Guiding and /or dithering between several exposures will reduce this significantly.
Let me know if you need more help ;-)