Hi. I use your plugin in every project. I think this is an excellent and simple management solution robots.txt .
For the same reason, when I wrote my plugin for generating meta tags, I did not make an all-in-one harvester.
But now I have some doubts about the tabs in the settings.
I'm currently using a bunch of CatDesign plugins.SeoCore + Rainlab.Sitemap + Zen.Robots.
And the settings of the SeoCore and Sitemap plugins are located in the system::lang.system.categories.cms tab
And Robots has its own SEO tab.
And in this case, the SEO settings are scattered across different groups. Let's change the tab on your settings page to the system system::lang.system.categories.cms.
I would send you a PR myself with this change. But I don't see a public address with a repository.