I love the idea, but I have one concern, which may or may not be real. I think 5% is below market rate for what you are doing. By establishing 5% as the rate, you crowd out any local investment options which would need to charge above 5% (but not 60%). By making the subsidy non explicit, you make it even harder for local lenders to compete. I don't know what a market rate for this kind of loan would be, but in the US…
We allow borrowers to offer any interest rate they wish, up to a maximum of 25%. Lenders are then free to fund the loans at any rate up to the maximum offered by the borrower. Many lenders opt to fund loan applications at well below the offered rate, resulting in an overall average of around 5%.
We have not taken a position on the "optimal" interest rate, other than limiting it to no more than 25%. It will be interesting to see whether the average interest rate changes over time and as we continue to grow.