Wow, interesting discussion. I wanna share my opinion too :)
First of all, I totally agree with why Morgause had to be the one sacrified instead of any random man? To close the veil the dorocha only need any random people to sacrifice himself, it is logical to think that to open it, only need any random people too....
I liked Morgause, she should appear more. But after Morgana became villain and powerful, she just had to disappear I guess. So the focus will fall only on Morgana. Too bad...
The next thing that also crossed my mind : why was it so hard to kill Uther and Arthur when Agravaine could do it easily with poison or even stab them in their sleep since he had access to everywhere? Nobody will know who did it or being the right hand of Arthur he could easily pointed his finger to any servant or guard and everybody would believe him.
But I guess if that is done like that, then there will be no interesting drama to build over and over again throughout the series :). While I think the whole series was almost always about how to kill the King, Uther (and after that Arthur) in so many interesting but stupid and impractical and inefficient ways. Then there is no use of Merlin too if they died just like that. :p
About Lancelot. OMG!! I can't believe that he had to die so soon and like that. I think everybody is right to say that he was not involved enough in the show given that he was the most noble and the bravest knight of them all. Sorry for fans of sir Leon, but I have to say this, why keeping Sir Leon alive again and again but not Lancelot. Sorry to say this (again) but in the legend sir Leon was nobody compared to Lancelot, right? or in this case any other knight too. He should be the bravest and most noble knight, but when did he get the chance to show that? Only in this episode when he sacrificed himself. Not enough appearances. If sacrificing himself made him that, I think every other knight would gladly lay down their life to protect Arthur too, over and over again.
And to make Lancelot returned and had a fling with Gwen under spell for me just plain stupid. Not making any sense and was not a good thing at all. It will be much more interesting and meaningful if Lancelot and Gwen had a fling because of their own feeling, not because some stupid useless spell. But yeah, I know why the producers decided this way : so Merlin can save the day again with his spell and to save Gwen's and Lancelot's reputation because it was not their fault! Because Gwen and Lancelot must stay oh-so-perfect-and-noble.
About Agravaine, when I first watched him appeared out of nowhere and suddenly became the most trusted person at Arthur's side (just because he said he was his uncle), I thought I have lost some episodes from the DVD I bought. I thought, OK, I must missed it somewhere, where there must be some explanation or at least hints of who he was and where did he come from or how he became the most trusted person of Arthur. But I didn't miss it. It just Agravaine just *poof* appeared out of thin air. LOL.
And Gwen. I very much dislike her in this episode. She took care of Uther not because she was so noble and forgiving and kind hearted, but because of Arthur. But everyone seems to see her like that. Or at least that was the image about her we should believe. If she was so noble and kind and forgiving that meant she could become a great queen and would be accepted although she was a servant. And has anybody noticed that her outfit just become more and more sexier? Her breasts almost falling out of her gown, and her gown getting tighter and tighter each time. Hmm, I think this was purposedly done to make her even more acceptable unconciously (she is kind and sexy. What do you want more from perfect queen? :))
Anyway, what I like about this episodes : The interactions between Merlin and Lancelot. I always love to see those two together. I am so sad there were just too few episodes with both of them bonding.
I also like when Merlin didn't have his magic and couldn't do anything to save the day like always. He had to be brave and fight with his own two hands. Admitting that he was scared but still willingly fought and defended Arthur with his life showed his true courage.