1. I can't think of many good reasons for memorizing an address. Anyway, sometimes transferring an address between devices can be cumbersome, but usually it is not a problem and there are ways other than writing it down. Some sort of address registration service might be helpful, but if it were really necessary, it would have already been created.

2. The problem with being able to get your money back when you make a mistake is that you can also get your money back when you don't. It enables the kind of serious fraud that banks and credit card companies have to deal with. If you need a third-party to validate transactions, then you have eliminated the main advantage of a cryptocurrency.

It seems like what you are asking for is a banking system and debit cards. That has all the features you want and it already exists.