My impression watching the show, and I'm a fan of both don't get me wrong, is that Smallville owes a tremendous amount to Buffy the Vampire Slayer, and is very much a superman version of Buffy. I bold the most impressive similarities.
- Start off in high school for a few years
- Go to college for a bit and then they drop out because of their fantastical duties,
- Have a female friend that turns into a witch,
- Have a long and tragic high school romance, but end up hooking up with their true love (Spike, Lois) later on, lovers with whom they started off as "enemies"
- Start off with a supervisor (Jor-El, Giles) whom they outgrow
- Have a brief arc of the government getting involved, the initiative in Buffy, and now Checkmate in Smallville
- Have identical episodes. "Labyrinth" is a direct copy of "Normal Again", both season 6 episodes in their shows. They both have a one-off insect-person hybrid episode in their first few episodes, who goes romantically after one of their close friends.
- Buffy runs away at the end of season 2 after she kills angel and spends time in Los Angeles. Clark runs away at the end of season 2 after he kills his unborn sibling, and he spends time in Metropolis.
- The end of Buffy was somewhat confusing due to the presence of numerous potential slayers. Smallville is currently confusing due to all the Kandorians.
- All the other slayers in Buffy either die or become problem slayers. All the other Kryptonians in SV either die or become problem Kandorians.
- Buffy's mom dies in season 5 in a predictable tragedy, the other parent is still alive but doesn't matter. Clark's pa dies in season 5, in a predictable tragedy, the other parent is still around but doesn't matter.
- Buffy focused on vampires and freaks of the week in seasons 1 and 2, expanding to different mythology enemies in season 3. Smallville focused on the Luthors and FOTW in seasons 1 and 2, I think we meet Morgan Edge in season 3, and later on Brainiac, Doomsday, etc.
- There's a single bar/pub where everybody in Sunnnydale hangs out: The Bronze. There's only one place where SV people hang out: the Talon. Since SV is aimed at the CW crowd it's a fancy coffee shop that serves mocha java frapuccino lattees with whip cream rather than a dive bar.
- For both shows, season six is season sux.
- Apocalyptic high school graduations in both shows.
- Buffy dies in season 5. Clark dies in season 5.
- In season 5 of Buffy, "perfect" Riley Finn develops addiction problems, and goes to be sucked by a vampire, in part to overcome the lack of intimacy he feels from Buffy. In season 5 of Smallville, "perfect" Lana Lang gets injections of krypto-death, to see her dead parents and in part to overcome the lack of intimacy she gets from Clark.
Looking at this list, what's kind of sad is I'm not sure of any point where Smallville did a better job.
- Willow's witch arc was much more interesting than Lana's.
- Xander > Pete Ross
- "Normal Again" > "Labyrinthe"
- Buffy's mom dying felt more tragic than reckoning
- When Buffy ran away in season 2 finale, she came back on her own. When Clark ran away, both his fathers made him come back - I'm not sure which is more interesting.
Smallville > Buffy:
David/Doomsday is like Ben/Glory