It's not that we don't know the answers to your questions. I have an RGB-modded PCE that I play on a Sony PVM. Every single game looks crisp, clear, and colorful. Yours apparently doesn't. My mod was done by the book, yours wasn't. Do I need to connect the dots for you?
Edit: my buddy has the exact same monitor as you, and everything looks fine on his, so since your Neo looks fine on yours, it isn't the monitor, either. I know that building the amp sucks, but just bite the bullet and do it, then let us know if you still have problems.