Looks like the other thing that Canonical decided to re-invent is puppet (or Chief)

From the look of the remarkably content free description, it looks like Landscape is a low featured closed source monitoring and remote control tool for Ubuntu servers with a pretty GUI

Puppet and Nagios are both open source and fully featured, the problem (in my experience) is that they can be tricky to configure without a fair investment of effort, making them not worth it if you only want to manage and monitor a small number of computers.

With that in mind, perhaps the best way of improving things would be to develop a simplified wrapper around Puppet and Nagios, that replaces many of the complex stuff with simplified defaults, so that an admin can get a basic setup working quickly and easily.