I love the featured image!
As for the event,
It be neat if we got gen 3 because they code is practically complete iirc, but that's unlikely. Hopefully it's a change from last year's Sure all those pokemon were great but now most players have them so hopefully spawns aren't overbearing if increased.
It be cool to get a Halloween Pikachu and some rarer Pokemon to spawn in the wild. Only time will tell though.