I would agree also that, you are off to a great start Martin - beautiful spot for flying and filming and you got some amazing footage.
For certain try out ND filters, a little "jerky" on the gimbal moves - but hey, first time not bad at all, smooth that out a bit and you're ok.
Best tip of all is now that you have that great footage - get yourself some editing software and all those "jerky moves" you can edit out of there with nice smooth fadeouts for scene changes. By the time your finished editing you might have about 1/4 of all that footage and a neat and tidy 4 - 5 minute video (maybe even two of them).
Good job - keep up the safe flying and filming (learn some editing - it's a lot easier than you would expect) and you will really see your work come together.