My vote would be developers and more people from the community. I like the idea of giving people a chance to talk about there cool automations or how it fits into there life.
People with different careers tend to both see and use automation differently. Running the full gamut of a BA with a pile of excel macros to do the job, through keyboard maestro experts right though to developers who just role there own systems.
As an automator and developer, I wouldn’t mind voicing my opinion on the show. 
In addition to guests who stay on for an entire episode, it might be interesting to have some guests from the community who come on for 5-10 minutes to share one workflow. This could either be as a regular segment related to whatever topic that episode is covering or do an episode composed of just a series of these short guest segments.
How about some speakers from those daily tools we can’t live without…Evernote, assana, atlassian, omni focus, hazel, text expander, keyboard maestro, scrivener, Drafts, Fantastical, google (everything ! ha ha).
I would be really interested in hearing their automations for their tools.
Someone really deep on security was well for MacOS and IOS like Kevin Mitnick.
Kevin Mitnick!! That is a blast from the past. Wasn’t he one of the original “fone hackers” like with telephones and Baud modems?
The Linux Subsystem for Windows seems to offer some interesting options. I did a bit of work with it at one point, when I was living a more “OS promiscuous lifestyle” 
Scott Hanselman (https://www.hanselman.com/) might be able to speak to this area or suggest someone who could.