Hi Steen,
I am currently listening to the final mix.
On the whole, I think you should be proud of what you have done here. You say, "it's not going to get any better," but I disagree a little... Okay, leave this one where it is, and then apply what you have learned on your next project.
To be honest, I think you have a fine song at the end there. You have a good voice too...
cheers
andy