goodness knows I'm not expert on the stink'n 5k but....

why don't you try a slow start. the beauty of them is that there are many...and sometimes you need to play with them to find what works for you.
did you read that art I put into training section by McMillan? I think that explains exactly how you should run a 5k.
I also think that a fade is too be expected. that if you are not fading somewhat then you are not running to your best ability. the real trick is to dial in and hang on.
another thing I think is that you are never going to be happy with what you have right now. As a runner we always look back and see what we could have done should have done that sort of thing. As long as you are honestly doing your best...then that is your best. for now.
another thing...glad I chimed in eh? it is stink'n hot out there this summer. hotter than normal...wait until fall...I promise a sweeter time. the perfect race has to be given to you by the gods so to speak....if you are trained right then the rest is up to the running gods. the gods are happier in the fall...more people training for long races