Block erupters are not profitable.
Yes I know that, I'm not buying them to make ROI solely from them. Maybe you should re read the post.
Nowhere does it say why you think that buying Block Erupters will be a good idea.
The facts are very simple. If you have 1 BTC and you spend it on BEs, you will receive less than 1 BTC of mining income. Sure you can use what income you get to invest and try to profit from investments. But if you just kept your 1 BTC and invested it immediately you'd have more BTC.
Your offer of 5% of the loan as collateral in the form of BTC is pointless. The whole purpose of collateral is something for the loan-giver to keep / sell when the loan isn't paid back. Consequently, the value of the collateral needs to be at least as much as the amount loaned for it to be useful.
I understand what you are saying but I think you're not putting what I've posted into context. I've added some text to help clarify.