Welcome to the game reports section of the forum...
I agree that you played the second game really well. Engine won't work here, and your opponents play doesn't make too much sense.
If he does mirror you, I think your 3rd bridge is a bit too much. Maybe Silver+crossroads in stead? That only works if you plan on buying the bridge in turn 4 during your turn 3 though.
The first game... yes it's an engine, yes someone will megaturn at some point.
You already explained why it is far from ideal (no trashing, some junking).
However, there is no means to end the game without the megaturn, and KC is very explosive, so you'll just have to go for it.
Try to go off before your opponent does. I.E. Add Kings Court, Rabble, Mining Village to your own deck, and use Swindle/Jester to disrupt your opponents.
I don't like your opening village, that's only a good plan if the components you want are really cheap ($3 with some good $2 cards).
Here they cost $5, $4 and $7, so I'd open Swindler/Silver.
I also disagree with your trashing of villages so early.
Stay away from buying gold, platinum, treasure maps, green cards... well you already did that.