This event is certainly looking better than the big 10.
Personal highlights:
-Rune drop rate increased.
-Guaranteed Cosmic medallion and ring from cosmic doops.
-Random 10-30 minute significant RIF boosts
-Chance for hero tokens (although will probably be as insanely rare as costumes... aka. I won't find one)
So what's a good place to farm before it's nerfed? What has the most enemies? Maybe spam a particular terminal? I'd think Midtown but performance there would probably slow me down, it's hit or miss there for me. Sometimes it's ok and other times it's slide show at TGI Fridays.
Midtown has a good amount of enemies, but requires fast/constant moving to make the most of it since groups of enemies can take a while to respawn. I don't know how it is now, but lower asgard fountain had crazy good spawn rate without needing to move, which is why people were farming cakes there before the nerf. As for terminals, I don't know if there is any in particular that is better for farming. Kingpin's has a clear, simple layout that is great for ranged heroes. Other than that, Juggernaut, MODOK and Doctor Doom have the highest enemy counts. Juggernaut would be good if you don't have the Unstoppable Force recipe yet.