It sounds like a pretty cool event. I've caught Drowzee and evolved one to a Hypno, but I wouldn't mind catching more of them since they're so rare around me. The Gastly line in particular is quite handy too since I've only hatched two Gastly up to this point. Being able to capture Gastly and Haunter would be quite useful, especially when trying to get all the way up to a Gengar.

The candy bonus rewards for everything else sounds awesome too. I'm so close to getting enough candies to get an Exeggutor, but if I can get to that point faster and possibly make a large dent for at least one other Pokemon like a Horsea or Grimer as my Buddy Pokemon, then that would be awesome. I hope that they have these kind of events more often since it would make evolving Pokemon so much easier and less time consuming. I wonder if we'll get more candy when we hatch Pokemon during this event as well.