But I would like to point out that everything you mention can also be obtained through other avenues. Although in your case, as an artist, Facebook may be more valuable to you compared to other people...
Facebook is not the be-all, end-all of online communication and conversation.
There are news outlets, community groups, in-person groups, associations that can be joined to stay updated, listservs/e-mail updates, forums, etc.
I also take issue with the "used sanely" part because I don't think Facebook is a medium that promotes sanity for all people. There is a lot of narcissism, highly filtered and biased (mis-)information, infotainment, superficiality (in addition to the benefits you mention)...Granted, these problems are not at all solely limited to Facebook (and in many ways are rampant on the Internet, especially since the Internet was practically hijacked by marketers and advertisers and e-commerce "entrepreneurs" looking to make a quick and relatively easy buck). But Facebook seems to concentrate these problems.

If Facebook works for you and you can avoid the negative aspects, great, but no one can deny that there are people for whom being off Facebook is "just fine" as well.