The discussion with the final four in a circle towards the end sounded really off.
The lets-omit-the-big-idea-and-reveal-it-later-over-a-montage gag (ala 5x22) didn’t seem to have a purpose.
Angel goes as quickly as he comes. You renegotiated the crossover deal for this? And why not mention that they have the power of Wolfram and Hart to do whatever’s needed? And since Buffy doesn’t know this, does she really thing Angel’s going to be able to stop a corporeal First Evil?
Why not have Willow do the spell at home or before they charge into the Hellmouth?
Why are they so concerned about ubervamps getting out? What are they going to do? There’s nobody in Sunnydale, and it’ll be hard for them to get out of it in the middle of the day. Is whatever damage they’ll do really worth sacrificing the non-slayers over?
They sure are all having an easy time dusting those ubervamps. The script says they merely hold them off, which seems much more realistic.
Buffy’s idea for battling the ubervamps is stupid. Does she really think 12 slayers can’t can take on the giant ubervamp army? If not, why is she releasing them all now?
There are lots of better ideas. Why not just blow a hole from the sunlight to their underground cavern and vaporize them all? This would also prevent them from escaping (unless they can jump really high). Or, if the Hellmouth is only accessible through the seal, use a giant mirror to reflect sunlight into the cave. Or just bomb the place into a big hole.
Spike’s death was hardly a sacrifice. It’s unlikely that he thought the medallion would kill him and it was suicidal not to take it off after it vaporized all the vamps.
Where’s the resolution for "From Beneath You It Devours" or "Buffy won’t choose you, she’ll be against you"?
Why is the First Evil just waiting down below with all those ubervamps? How come only one ubervamp came out last time they opened the seal? And how come that ubervamp had to wait for a long time (until a full moon?) before going after Buffy? These ubervamps sure didn’t.
How did all those ubervamps get there? Do they breed or something?
On the bright side, as Derek Powazek points out, the show provides resolution to its two major themes: