I try to deinterlace last, unless the NR filter insist.
Color/levels are be tricky as well.
Sometimes the correction adds noise, but then you don't want to correct (for example) chroma noise.
Avisynth has no one-size-fits-all scenario.
Be careful of source bias, due to your usage: VHS, Hi8, film, Youtube, unknown sources, etc. It's why I general mention, as much as possible, that my use of Avisynth is almost exclusively for VHS work. Almost.
But I'm sure stevevid is getting good info from all of our input, he can see varied preferences.