Generally, investigators requesting support for surveys or interviews should submit protocols or equivalent information and credentials with the proposals. Consider dividing an ambitious project into phases. Whatever methods are used, explain how the project meets relevant standards for evidence and interpretation. Explain how your methods provide support for your hypotheses or your interpretations, and include the qualifications of project personnel to develop or use the methods. If you need additional expertise, recruit a consultant, co-investigator, or advisor.
Many methods have merit.
It is often necessary to use more than one to arrive at reliable results. For example, archival research might supplement ethnographic fieldwork. Funding constraints may limit investigators' methods. If so, a proposal should discuss these limits and plans to ameliorate or overcome them in future research. Methods for philosophical and policy analysis are often difficult to describe.