I haven't actually watched that many Merlin vids, but I have noticed a certain trend in my enjoyment of them. There are good serious ones: deep meta, tragic possibilities, hardcore shipping. But the ones I prefer tend to have a fair amount of crack in them. Here are some examples!
Beverly Hills by
giandujakiss - Gen. That's where I want to be, living in Beverly Hills Camelot.
Just Dance With The Memories by
solanyxe - Merlin/Arthur. Reincarnation vid with anonymous sex and recovered memories.
Guinevere by
la_esmeralda_ - Gwen/Arthur, Gwen/Lancelot. Legendary damager, round table manager.*
Arthur Pendragon (Put A Ring On It... Seriously, Dude) by
neptune47 - Arthur/Gwen, Arthur/Morgana, Arthur/Merlin. If the previous vid was Arthur's lament, this is everyone else's response.
*Someone needs to make sure that Bradley James hears this song, btw, because he would walk around all the time singing it. "AN-gel is a HUSS-y, MER-lin keeps SE-crets, I feel BETRAYED!"