Building a great API is much more than picking the right tech, the quality of an API is driven by the quality of the documentation, upgrade path, libraries and the consistency and execution of the API. However, bu chosing the most applicable format you can get a great start and best position your API for the consumers needs.
A project can fail before it even starts. If the project estimates are off, nothing will save the project team from pain or at the worst prevent the project from failing. Through years of experience and failure, I've honed guidelines to help me ensure that projects I estimate can be completed within time and budget.