Some won't like my suggestions, but you asked.

My responsibilities: As owner my desk will be among the employees and execs will not have offices. I will of course have a modern, quiet, fuel efficient private jet, but I will let ALL employees ride along for time sensitive meetings that they are required to attend. I will hire veteran combat pilots. My jet will have Starlink Internet and we will utilize EVTols to go from the airport to the front door of our destination after I get exemptions from the FAA. Employees that are on-call would benefit from my insurance rider meaning they will not need their own auto insurance as long as they are employed by me. The break room and cafeteria would be full of a wide variety truly healthy foods at no cost to the employees. Unhealthy foods would not be free. Every employee would have the highest quality possible health insurance plan and would be 100% covered by Twitter. Every employee gets RSU's based on their role/position and have the possibility for yearly bonus RSU's based on quantitative performance. Employees that participate on a regular basis in the daily stretching and calisthenic exercises would earn additional RSU's, yes even if done over Zoom or TwitterTok.

Work-From-Home/Remote: Would be an option for nearly everyone. If Zoom is not good enough then a team would find a way to implement VR. All levels of leadership would be required to attend training and be certified to manage people remotely and improve performance through positive incentives. The tooling in the company would be updated to accommodate every aspect of remote management. Obviously datacenter operations staff would need to be at the DC but we would find a way to make improvements to their quality of life as well.

General Platform Changes: I would require my staff to modify the site to be more like HN and find good balanced moderators like here on HN. Anyone can post, even new members but their name will be green early on. People that constantly troll would start with negative karma per-post until enough trusted members upvote their content. Karma would only influence feeds but would not block posts nor would it endanger the account itself. Karma would never be influenced by Twitter staff.

Check-marks: Colored check-marks go away. Anyone can be verified regardless of how popular they are. There are already plenty of popularity contests in grade school and the workplace. Government issued ID, that's it. Verified. Done. No more "celebrities". Everyone gets equal treatment as a verified person. If a celebrity wishes to avoid abuse from us plebs they, like anyone else, can adjust settings in their preferences, meaning anyone can have the same settings that a celebrity had and conversely any celebrity can freely interact with everyone else if they so wish. Accounts that are operated by celebrity managers or agents and the like would have an icon explaining they are not operated by that person.

Layout: The UI and API would give people the option to customize every aspect of the site layout. Everything would be a module/widget and everything would be optional. Make it as heavy or lightweight as one desires. One could even access the site with a text-only browser and some of the site would even work without Javascript.

Editing: Anyone may edit or delete their posts without time limits. There would be a simple REST API members can utilize to do absolutely anything, with sane rate limits of course. The performance teams primary goal would be to make those rate limits as high as possible, meaning that what is considered "abusive API usage" today would be considered "normal" in the future.

Censorship: Would be a terminating offense. Anyone found censoring a persons post that did not explicitly and clearly violate laws by intent would be fired without warning and never allowed to be re-hired. Entities that attempt to pressure the company into censoring something would be publicly shamed. Anyone accepting bribes/lobbying would meet the same fate, possibly including their directors and VP's.

Pro-Censorship: Groups that are not happy about the lack of censorship could have their own managed Twitter think commercially supported Mastadon that has their own rules and their own moderators. They may censor absolutely anything within their group-rented instances. Anything that violates US law would still be handed over to the Global Trust and Safety Team. Any member of the group can "boost" the instance similar to the way Discord operates.

Trust and Safety team: I would stop hiring people that can be mentally damaged by intense content and instead hire from the 4chan user base exclusively. They would not even see it as work. All of that content would be moved into a pool where they and agents can review it. Even the people uploading that content would not be silenced. Rather they would be visibly only to their circles of friends and given all the rope required to make a solid case against them. This would be for content that explicitly violates the law of the country Twitter is headquartered in. Other countries would not be permitted to influence based on their laws and instead may block access or acquired a Twitter franchise to be hosted in their country if they so wish. My forensics teams that assist federal agents would be tasked to primarily focus on finding the true source of the content rather than focusing on the people that share said content.

Nations outside of the US: Nations outside of the US would be given the option to have their own Twitter franchise that is operated under their laws, operated within their nations borders. Think of this like Mastadon, but operated by a Twitter franchise. Like the US version, these franchises would also not censor anything that is not forbidden by their nations laws. DNS, Anycast and L4/L7 routing would be set up to accommodate delegation of Twitter to a country that purchases a Twitter franchise. Lawyers from within their country would be hired to operate their trust and safety team.