A lot depends on the local office where she resides. If they process stuff quickly, there might be an advantage. As folks have said, a marriage-based immigrant can apply for citizenship two years earlier. However, keep in mind that such a GC is conditional for the first two years.
What might be an option is to file an I-130 immediately after the marriage, but nothing more. If the I-140/485 get approved before the I-130, great. If not, then they can decide at that point if they wish to proceed via marriage based for faster citizenship and independence from the employer, or employment-based for independence from the spouse.