That actually depends upon your bandwidth (a point I was trying to make before about China which seemingly you missed).

Again even Satoshi did not think that home nodes would be needed so I don't know why you think they are (provided we have enough miners we should have enough decentralisation).

If you really want a network of just CPUs from home computers or the like then you don't want to use PoW (maybe you should look into PoS or PoC or the like).

Also please make sure you have read this: https://en.wikipedia.org/wiki/CAP_theorem to understand why Bitcoin can never be as efficient as a centralised service.

Please think about the fact that Bitcoin has *failed* to gain any significant hold in the remittance market - as all logic and economics says it should have (and I do know major players in this area). If it can't succeed in that then I think hoping that it has any chance against the major payment systems is actually just fantasy.