Yes, this is a good suggestion, and one we have fully investigated.
Unfortunately, cloud hosting does not work for heavily-loaded database-driven sites because you cannot add another server 'on demand', as with an HTML site. There are impossible issues with database synchronisation, since every DB has to be synced to every other DB every few seconds. In practice this is impossible on a heavily-loaded site since it doubles disk activity (or more) and means the site slows to a crawl, and disks burn out fast. Each DB has to sync with every other DB and it all ties itself into a knot.
Cloud hosting cannot be used for this type of site at present. There is a way it might be utilised in the future, perhaps when the whole system is developed more: you might be able to feed the DB on a powerful, regular, dedicated server to webservers in the cloud. Somebody might be doing this now but I don't know of a service that does. We don't currently need this, as our configuration works OK, it's more of an economic issue than anything else, perhaps when we have that many web-facing servers and load balancers that it becomes necessary to look at the cheapest way of running the web-facing boxes.
I do run cloud-based sites and the technical issues don't go away, unfortunately. Just last week we lost a cloud hosted site, because the servers went down due to a power issue on both the server and the backups. The trouble is, the site has to be on a server somewhere, and in the end it's vulnerable to power issues. In theory that can't happen to cloud sites but as I say, last week it did - which scotches that theory
Currently, cloud hosting is good for simple HTML-based sites, CMS sites without much content changing, and servers running various sorts of web tasks. Unfortunately it's no good for modern, DB-driven sites if they are heavily loaded. Maybe with less than 5,000 visits a day or something but we passed that point a long time ago.