Really cool shots man! I love taking long exposures of the night sky, especially time lapses, though I've never tried to get warp from the stars by doing a super long exposure. It's a great effect though. Well done. Why do you say you should've done higher ISO? Looks like you got enough light even at the lower setting, with minimal noise.
Here's one of my favorite night shots I've captured:
I was aiming to get the Milky Way in the shot. It's there, but it's blurred.
When going for that kind of shot, you have to turn all sensitivities to full blast so that it's possible in post production to pull it out of the haze.