I'd like to see a season that answered all the unanswered questions from previous seasons.
Why does Buffy wear a winter jacket, and a double-knit, turtleneck sweater to go walking in the desert?
How does Buffy afford all those pairs of Pyjammas.
What happened to the Pig? Does Andrew eat pork, cause you know, "killing pigs is just wrong...and hard".
Why do all the people of Sunnydale all of a sudden get up and evacuate on a particular day, when they'd already suffered years of demons, vampires, werewolves, and such. And why would anyone choose to live in Sunnydale anyway?
Why did the small town of Sunnydale have such a large police station, and what did Sunnydale cops actually do for a living?
How is it all these strange occurrences happen in Sunnydale yet no-one from Extra, or the National Enquirer ever shows up?
How do vampires shave without leaving a whisker? They can't see in a mirror. Why do you never see a vampire with a beard? Does their hair grow?
If Willow can just pop things in and out of alternate realities in Season 6, why doesn't she just do it to every bad thing in Sunnydale?