The second episode was 1 hour and 20 minutes of seemingly random shit that all conveniently came together at the wedding.
But it wasn't random - it all led towards something... and so was part of the plot.
I can see why people didn't enjoy the first episode - where the mystery plot was very much tacked onto the Sherlock is back plot - which people find less interesting. This though, the Sherlock is best man plot AND the mystery plot were woven into each other thus making the mystery a big part of the story. I found it to be very well done, but even if you didn't, I can't see how it's "random shit" as it all clearly served a purpose.