5. Offer hardware support that's second to none. So far, Linux leads the Unix pack for hardware support. Sun can do better. It should be using its clout in the industry to get high-quality drivers running on Solaris for as much mainstream hardware as possible. Solaris should run on laptops just as easily as PCs. Solaris-powered graphics workstations should be powering the motion picture effects industry. No one should have to think twice whether they can install Sun's OS on their hardware.
6. Become the OS of choice for developers. There will always be a market for Visual Studio, but Sun has a chance to capture the developer market for enterprise apps outside the Windows world. Sun should throw its full efforts into developer tools and make Solaris a programmer's heaven, out of the box -- even if it means ditching NetBeans for Eclipse.
7. Virtualization all the way. Containers are a rock-solid implementation of virtualization for Solaris servers, and Sun is already offering to make Linux a guest in its home with Containers for Linux Applications. Why not do more? A VMware-like full virtualization solution shipped with every Solaris install would mean nobody needs to give up their other OSes to use Sun technology -- even if those OSes include Windows.
Got any other ideas? Drop me a line.