Season 4 under season 7 is a tragedy. The Xanya goodness alone makes it better. Plus you've got a coherent theme and arc, a competent big bad, more sets than just Buffy's house, no Rona, and how about that Xanya? The origin of break up sex, the hand signal in Hush, "orgasm friend", Xander living in a basement, romantic syphilis, bunny suit, stand up about ducks and more! Season 7 just has bitterness, eye injuries, a little break up sex and death. You can't compare them. Did I mention Rona isn't in season 4?
Once again, you are biased.
However, season 4 just doesn't do it for me. The only thing I really like about season 4 is Spike.