I was checking out some keywords and found a niche that has very low competition in the SERPs in terms of everything except domain authority. There's Ebay, Amazon, and Yahoo Answers to name a few. The domain authority starts at 64 and goes up to 100, and the sites' ages are from 8 to 15 years. Most of the pages have a PA of 1 and many have 0 links.
Is this a niche I should consider getting into or am I crazy even thinking about it?