Does the blessing of the Prophetic supplications differ with slight variations in their wording, and is scrupulous adherence to their exact wording considered excessive veneration?

All supplication is good and blessed. It is best to supplicate with the wordings that have been authentically reported from the Prophet (peace be upon him). In specific supplications, such as the adhkar for sleep, the wordings should not be changed; rather, they should be recited exactly as they were reported to realize their merit. In the hadith of Al-Bara' bin Azib, the Prophet (peace be upon him) taught the supplication for sleep and rejected changing "and Your Prophet whom You have sent" to "and Your Messenger." The reported wordings yield their merit by being recited exactly as they were reported. Whoever changes them will receive a general reward, but will not attain the specific reward prescribed by Islamic law. This is unlike the Quran, which is not permissible to change at all.