^Uhm... yes.
Well, second only to Buffy.
Your point being?
Point is, Joss Whedon is a great entertainer, but it's all window dressing. Characters and plot are reactionary rather than planned. That doesn't make them bad (I really enjoyed Firefly), but he misses a depth - much like Lucas does. Which seems odd considering the incredible world Lucas created and the tangled story. The problem was, he laid out the plan as a fantastic arc across the two trilogies, but then couldn't join the dots. I find Whedon is similar, he has a plan, but spends too much time on the "now" and then dealing with the consequences later with plot/character twists.
If you look at the other two big Sci-fi contemporaries of Firefly (well, close enough), Babylon 5 and Battlestar Galactica - they have story arcs that affect the characters and plot deeply and intrinsically from episode one - sometime you don't even know that the plot arc was there or the twists were there until episodes or even series later. It's the long game. Having said that, on an episode by episode basis, Firefly (and Serenity) are much more watchable and entertaining.
Which is why I mention it, because ESB is the long game in the trilogy. While it does have moments of action and silliness, it's laying down the tendrils of the universe and for the first time, showing us a much bigger picture in the Star Wars universe. ANH is brilliant (and laid actual rules down for how to make films - seriously, there's a document going around Hollywood that unpicks what Lucas does and says "want to make a good action film - here's exactly how Lucas did it - follow this and you'll have a hit") - however, you're on a rollercoaster ride with the characters. Their actions are forced and they literally just ride the story out without any real free will or chance to act on their personalities. This happens to a degree in ESB, but we get to see the consequences (both physical and emotional) of character decisions which gives them more depth than you see in any of the other films. The film feels much bigger than it actually is. That's just one reason why ESB is the best of the bunch, but it also has much more epic and better presented scenes.
You can break down the films into their memorable set pieces, and if you look.
ANH: Droid escape from Tantive, Jawas, Sand people, Cantina, Death Star rescue, Death Star escape, blow up death star, medals.
ESB: Wompa, AT-ATs, Asteroid Field, Meet Boba Fett!!!!, Yoda, Bespin, Jedi Training, Han gets frozen, Jedi duel, Father reveal, miserable end.
ROTJ: Rancor, Leia in bikini, Yoda dies, Teddy bears, Force Lightning, Teddy bears, Not David Prowse, Teddy Bears, medals.
TPM: Dull ****, pod race, dull ****, Jedi Duel ruined by cuts to dull ****, medals.
AOTC: Lots of mixed action scenes - none individually memorable, floating food with worst ever CGI, riding cows = love, R2 flies, Jedi Battle, more Jedi Battle, more Jedi Battle, bollocks.
ROTS: Dull fight, dull fight, dull fight, fight that goes on too long, dies of broken heart, NOOOOOOOOOOO!
TFA: See ANH
It's clear that (and I will happily concede to people putting ANH top) the first two have the best and most memorable set pieces
As for my list - after watching Rogue One (R1?)
So the actual list is:
ESB, ANH, TFA,
R1, ROTJ, TPM (just - but it's bad) and ROTS (because it failed to do its one job). Witchfinder is right, 2 is best just forgotten.
Including the expanded universe (canon) I've subjected myself to:
ESB, ANH, any Star Wars Lego show,
R1, Rebels, TFA, Tarkin, ROTJ, New Dawn, The Clone Wars (animated film series), Lords of the Sith, Twilight Company, Aftermath, Aftermath: Life debt, TPM and then ROTS.