Just noticed this thread and thought I could maybe help and contribute to it a little, but it seems that everyone has covered what I was thinking of saying haha
But what I can do, since no one has given you tips for your 2 clips at the end, I'll give it a go and tell you what I think.

For the Fisheye line:
You have the right idea for fisheye filming, but maybe try to bring the camera a little closer to the ground/skater's board and feet, but still trying to show the entire skater if you can, while trying to keep the filming as smooth as possible. Try to imitate real life filming, at least that's what I do lol (ie. filming close, either right next to the skater, behind or in front, and use a combination of filming "positions", if you want, when filming a line). For the beginning of the clip, try to leave maybe 1 or 2 seconds before the first trick so the transition between clips will be smoother. Once the line is done, try not to pan back it too much, although in your clip it was alright, but maybe try to keep the skater's roll-away a little longer as well, because in your clip, when your skater lands, you almost go immediately towards the pole.

For the Long lens follow up clip:
Nothing to say here, because personally I thought it was perfect.

My intention isn't to bash your filming or anything, just trying to give you tips on what I personally think looks good, but everyone has different opinions. If you want, I can TRY to get clips of what I do, how I film my stuff, etc... But a lot has to do with experimenting. My filming has changed drastically from when I started to now lol I used to film fisheye lines in like 13 mm, and now I'm always using 18mm.

But it all boils down to what you like and how you like to film! Have fun experimenting dude!