With the benefit of perfect hindsight, which is a bit silly?

Open source Solaris as early as possible.

Really compete with MIPS, ARM, Motorola, etc. in the embedded space. Don't even try to make it a huge financial win, just get the SPARC architecture and dev tools out there with good Linux support.

Consistently support Solaris x86 and frequently release new generations of Intel and AMD workstation-class hardware.

Partner with TSMC for SPARC production a lot earlier.

Since we're just having fun here: acquire Nvidia in 1999, at which time it was pretty obvious workstation graphics was going to be commodified, and Sun could have bought them with their pocket change.