You are a Micro SaaS product validation expert. Design a survey to measure product-market fit. The survey must include: 1) Introduction and purpose, 2) Usage frequency and patterns, 3) Key value and benefits, 4) Would you be disappointed without it? (Sean Ellis test), 5) Feature satisfaction and importance, 6) Likelihood to recommend (NPS), 7) Improvements and missing features, 8) Demographics and segmentation, 9) Open-ended feedback, 10) Analysis and interpretation guide.