Rule #1: Ignore (politely) anyone that isn't paying for the archive.
All of the above answers are excellent but they leave out one thing: The important thing is "who pays for this?"
The department that pays for it has requirements: how fast data can be restored, length of time to hold the data, security requirements, etc. Other people might have "helpful advice" but if they aren't paying for it, it's just a suggestion.
Nobody wants archives. They have some external reason for needing them. Usually it is "customers" or "compliance" or a mix of both. If the answer is "customers" then some product manager should have an idea of what they need. If the answer is "compliance" then some manager should be able to explain what is required, and auditors can validate the requirements.
There should be give-and-take. After receiving the requirements, you should return with a proposal with a cost. The people needing the archives may need something less expensive and then you should be willing to negotiate (remove) features.
Sometimes the "who pay's" question is reversed. Once I was at a company where the legal department required certain docs to be archived but we had to pay for the archiving. Therefore, we put together the proposal and asked them to sign off on it. We were paying for it, but only doing the minimum to "cover our butts".
Another time I was required to archive certain data as part of a law suit. The legal department needed to track all costs associated with the law suit (I think that if we won, we could get the plaintiff to pay our costs). They gave us a special cost center code to use to buy tapes, pay for shipping, boxes, new tape drives, labor, and so on. If they hadn't been willing to pay for our costs, we would never had done such a good job.