I propose to be one of those computers storing the accounts and transactions. In fact I propose to store your account and transaction information. So pay me 0.005 cents for storing your account and I will pay you 0.005 cents for storing mine and those two payments cancel each other out. I know that algorithm works for 2 nodes, I think it works for N nodes.

Since most users in MicroCash won't be running nodes this isn't a zero sum game for the nodes. Apparently all running nodes are going to be paid a reward from the CPF through some mechanism. I doubt it's going to be "that much" though.
You are proposing to charge the providers of the service, the nodes are the ones storing the information and providing this "luxury". They provide this in order to verify that the block chain is correct, which in turns provides security for those depending on that correctness.
Everyone who has an account pays, not just the node operators. People who run nodes are generally going to be businesses, supporters and people seeking the utmost in anonymity.
Because there is no known way to pay nodes fees for running and providing the service in a decentralized manner MicroCash will be using part of the CPF to help support the infrastructure, which is a good use of it in my opinion.
That person running the node is providing the storage, network transfer and CPU usage that you are proposing to charge them for. So now it costs them twice as much to participate. If Microcash needs money to defend itself, it is not secure. If a authoritative group needs to collect these funds then Microcash is not decentralized. The power, profit, and motivations becomes highly concentrated in the accounts with the most coins. Coincidentally, you control the most coins in the block chain at the moment. Or is it coincidence?
Anyone running a node is storing the blockchain but they aren't the only one. Part of the reason p2p decentralization works in a security sense is the fact hundreds or thousands of computers store the same information. If your computer is corrupted you then go out to the other nodes who have it stored (storage cost) and ask them to send you everything (cpu and network cost). So even though you are storing it there is still a cost in those other hundreds of computers storing your information also.
Most people think putting a price on services is a good thing as it means it can't be taken advantage of. This is the reason for Bitcoin transaction fees after all?
In the Bitcoin model the miners get all the fees, why isn't this discussed as unfair? All the non mining nodes do the same work and they get nothing. At least in MicroCash anyone who has an account does get something back for all the network fees (both transaction and account). So this means nodes are paid indirectly for helping the network, the amount they get paid just depends on how much MicroCash they have.
The amount collected in daily transaction fees is only a relatively small amount, each account only pays half a cent, most real banks charge on the order of 100x more. So it's certainly not free like Bitcoin, but it's also much less than real banks. People have a choice if they think a daily half cent fee is too much or if they think that the biggest accounts are getting unfair rewards. If these two things are contentious to new users then MicroCash simply won't be popular. I don't see how these concepts are too negative though as they are similar to what people in the real world already deal with today (account fees and interest).
When comparing to real life banks a daily half cent fee is about 100 times less cost to a business. When comparing to wiring funds around the world a half cent fixed fee is about 6000 times less. When compared to buying items, you can buy something in MicroCash that is 5c and only pay a 10% fee for it, Visa/Mastercard would be jealous. MicroCash when compared to real life examples is extremely competitive.