As CEO I would strongly consider the Portable operating system interface $($POSIX$)$ followed by the instruction set of architecture $($ISA$).$ I would not consider changes to peripheral component interconnect $($PCI$)$ has a higher priority. The reason behind the ranking is simple, adoption. As a CEO of microprocessor and operating systems company sales are based on usage of the technology that the company provides.

PCI update though appealing, has a narrower effect on the market. A physical hardware update only occurs when the customer buys new device. In addition, the current market is trending more to mobile devices $[1].$ The market effect on a major PCI update would be much more limited$.$

ISA, like PCI would also have a much narrow market influence. A major update to the instructions set would be only likely be on newer next generation devices since making a major update to existing computer could likely cause significant issues and possibly crashes to legacy devices. This would be too risky.

POSIX on the other hand creates and opportunity for more developers to create programs that utilize the companies operating system. More programs bring more opportunity for customers to use the operating system. Dependency on applications for business and personal use means long term growth for the company. This tactic is not that different from what Microsoft is attempting to do with Windows $11$ and Google$$s android app platform $[2].$