Thank you for your feedback. In the future please create a different thread for each feature request, otherwise it becomes difficult for community members to vote for them.
SonarC# and SonarVB are already able to import Roslyn rules, including third party ones. See this documentation for more information. Is there anything preventing you from using this feature?
Regarding the creation of custom quality profiles, could you describe what problems you encounter?
The “Sonar way” quality profile corresponds to the rules we recommend and use at SonarSource for our own products’ quality. Thus there can only be one “Sonar way”.
If you want to see which rules are enabled by other projects, you can explore open-source projects on SonarCloud.
When a custom quality profile is created, we recommend to involve the development team in the process as it creates a feeling of ownership and trust. Developers will better follow the rules when they have specifically requested them.
Note that we don’t plan to provide quality profiles for third-party analyzers. As mentionned in the documentation referenced above, Roslyn rules are configured via rulesets.