I could speculate about the effect of minor changes in fore and aft trim, but it would be just that--speculation Some boats have a very carefully calibrated bow immersion, any deeper and they wallow, and any higher they come out of the water. I really don't think the Amel hull design is such that the line drawn on the plans is clearly better than one a tipped a little one way or the other.
When we first bought Harmonie, and she was empty of gear, she was on the waterline as drawn by Amel within a cm or so. She rides a bit stern heavy right now. Nothing in the way she handles indicates she has a serious problem with that. Her helm balance is easily adjusted with sail trim. I can work her upwind easily, and she is well behaved overall.
However... all that said, I am not now and never have been a racing sailor tuned in to the really finer points of tweaking a boat. I work hard and study to make her go upwind as best as I can, and pretty much figure everything else will follow along once I have that dialed in!
Fort Lauderdale, FL