Are the Reinhard options working right? I’m switching between them and fiddling and seeing no difference, well no difference from the individual settings anyway, on an HDR environment. A complete description of what the individual settings do would be good too, I haven’t been able to Google up anything.
Tone mapping is only used when there needs to be a convertion to low dynamic range values. In other words, if you’re using a HDR renderer like Brazil or Neon, it doesn’t make any difference.
It should make a difference to the rendered viewport though.