The ideal web hosting environment is that environment which provides initial cost-effectiveness, minimal ongoing maintenance expense, suitable performance for the application / site being delivered, security (including redundancy) to the level that the owner is willing to finance, and ability to scale in a manner that provides granular increases in expense and performance.
It's not any one thing.
What you propose, for example, has no geographic redundancy (it does propose redundant network connectivity, but one well placed tornado would take care of that). For some applications, that would not be acceptable (advertising-supported social network site), but for others it would not (credit card merchant processing services, financial services, hosted line-of-business applications).
Some business concerns won't need any level of redundancy at all, or won't be able to afford it. A single virtual server instance w/ a web server, database server, and SSH server is all that some web sites will ever need.
It's not a technical problem, really. It's a finance and management problem. If management has the money, us technical people can make anything happen.