Welcome to RetouchPRO Issy.
I would love to see your combined image before the application of the Impressionist filter to see if it matches my imagination.
In my opinion the filter effect is to strong and covers up to much of the background image, if my imagined view of the photo is correct.
You could reduce the opacity of the filtered layer over the original combined background layer or change the blend mode. I find that an opacity of between 30 and 80% and a blend mode of Darken,Overlay or Soft Light usually works best.
This is just my opinion of course.
Good idea on the combination of these images btw.