Sounds like you are an expert in hardware design and you have a deep intuitive understanding of the economics of that industry. You'll be able to sell your hackable routers for pennies more per unit than the existing companies--and people will be willing to pay that because you are giving them such a valuable feature (the ability to modify the firmware).
Why are you wasting your time with me? Get to work!
And, by the way, on what planet can you purchase a separate processor with its own flash chip for "pennies"?--even in large quantities that is absurd. You are talking a couple dollars per unit.