"How do we do X with this change?" is less clear if what you really mean is "This change makes X impossible". "Thank you for your contribution" is misleading when talking about a contribution that simply doesn't meet minimal quality standards. "Please" suggests that you consider something optional, which is misleading if you are actually expressing a requirement. Snide or hyperbolic remarks convey a message; perhaps not a welcome one, but one whose meaning is presumably intentional.