Hi,
I think two are great for starting out with night shots, but with a few tweaks, you could get the next ones to shine.
#1
I would stand further back, and offset it to the left of the frame. I would then take two exposures. One for the foreground colours, and another designed to get an insane sky. I would also choose my white balance in camera, to maximise some nice sky colours.
#2
Similar comments with regards to 2 exposures (foreground vs sky), but I also feel Arthurs Seat is too little a focal point at the moment, and this shot is way to wide. From that location, I would consider a telephoto for the job.
I quite fancy shooting down that way at night, I can give you a shout if I do it.
Gary.