Halloween event is one of the most fun ones but a huge issue is that it is totally based on RNG. A lot of people got really rich by just being lucky, and this ruins the game in a way. A person can be working hours everyday for months to make 20PL and then someone who is playing the game for a few weeks or months can get a Legendary worth 20PL and make all the work the other guy did just become useless, just because of RNG. With a lot of the features in the game making you work hard to earn items, having an event that gives you an insane amount of WLs based on how lucky you are is absurd. In a way its similar to betting.
A way to fix this problem would be making the Black Tower event favor hard work rather than RNG. For example, the items released each week can all be purchased with Candy, instead of randomly appearing based on RNG. For example, Rares can cost 100 Candy, Ultra Rares 300 and Legendaries 999 each with them changing each week as usual. This means that people will earn their items based on skills and time put in rather than just getting rewarded by RNG for nothing.