I like that for your feasibility concerns, you included more than just one concern because it shows that you took the time to think about the design and execution. Reading your concerns, I also like how you took into account the user and how they would interact with the product.
I wish you would have included a few sketches of the product ideas in your blog as well as your survey. Perhaps there could have been some miscommunications between just reading the title of the product idea and asking people what they would pay for that product because each individual had a different idea of the product envisioned in their heads.
What if you combined your “Scrubby Surface” idea and the “Dish Razor” idea so it could mimic an electric shaver? It would essentially be a sponge that could spin its bristles quickly to scrub off the crusted food from dishes.