I'm a gay man and I believe in equal civil rights for all citizens.
I'm in favor of a federal constitutional amendment that provides for civil unions that have the exact same legal status as marriage. If what you want is equal rights then that'll do the job and I support it. If what you want is to intentionally offend people that have a more traditional view of marriage then, well, I don't support that endeavor and you shouldn't be surprised that others don't, either.
No, that won't do the job, because it has been decided in this country, in another context and at the national level, that separate is inherently unequal. If you haven't done so already, I suggest you read the decision of the California Supreme Court that legalized gay marriage. It's quoted somewhere here on Bettermost, but unfortunately I'm not skillful at searching and creating links. A "civil union" is most definitely a second class institution. I don't wish to offend people either, but those who have "a more traditional view of marriage" need to get over it or deal with it, just as their ancestors got over "a more traditional view" of the role of women in society (like, they shouldn't be able to vote) or that it is acceptable for some human beings to be mere chattel. It may not be easy and it may hurt a bit, but I have confidence that they can do it.
I've gone on at some length elsewhere here on Bettermost that what I believe is that government needs to get out of the "marriage" business altogether, and clergy or religious authorities of any faith need to be deprived of the power of concluding legal "marriages." "Marriage" should be left up to religious belief. Only the government should have the power to conclude the civil contract of legally binding two people together. We're halfway there already in the requirement of obtaining a marriage license. And it should be obtaining the license on oath or affirmation that creates the legal union, not the words and signature of a pastor, priest, rabbi, or whoever concludes "marriages" in other, non-Judeo-Christian religions. So if you hold "a more traditional view" of marriage, that it can exist only between a man and a woman, fine, go ahead and believe it, and let it be your religious authority figure who conducts your "marriage." That ceremony should just have no standing in law.
The reason I don't support these efforts at the state level is because if you get into a situation where different states have different rules regarding the matter than you have a headache such as one I read about somewhere where some state (RI? VT? Don't remember) couldn't grant a divorce to a gay couple because the state where they wanted the divorce didn't recognize the marriage in the first place. To avoid that kind of incompatibility, any legal changes should be at the federal level.
You may find it strange, but I actually agree with you here. A state-by-state standard is unacceptable. There needs to be a national standard. What is needed is a court challenge that goes to the Supreme Court of the United States, which will have to rule, under the "full faith and credit clause," that a contract, even a marriage contract, entered into in one state, must be legally binding in other states.