The service is an ancient one, the main features of which are found in the 1st century and more clearly in documents of the 8th, 9th, and 10th centuries. It requires no revision to be in the fullness of Orthodox theology.
When was the Eastern service written, do you happen to know? Do the two services share a common ancestor, or were they entirely different from the beginning?
The crowns are an ancient part of the Western service but are not as prominent in that service as in the Eastern rite service. Therefore, the crowning custom sort of diminished over time in the West. By the end of the middle ages, often only the woman had a crown (wreath), and nowadays even that has been lost from the modern Western rites. By no means are they a Byzantinization of the service; the use of metal crowns for the bride and groom is mentioned by Pope Nicholas I of Rome in the middle of the ninth century for the Roman rite.
Hadn't thought about the bridal wreath, that's interesting.