The best upgrade I made for the Ender 3 for adhesion was a PEI coated build plate. I don’t know the specs of the V2, but the brand I went with was “Wham Bam Systems” mine didn’t have a magnetic bed so I had to purchase the kit with the magnetic plate, and stainless steel PEI coated build surface. It was nice being able to pull off the plate and pop prints off of it. Be careful printing PETG on PEI it can fuse to the PEI
If the V2 has some sort of leveling system make sure it’s working correctly or the PEI sheet isn’t really going to help. Mine did not. I had so many failures where the print head crashed into the sheet and gouged it. The Z end stop wasn’t the best. I added a BLTouch probe and flashed the firmware and it got much better.
It’s the same thing in the US. I see C-130’s flying in formation and think they’re probably training or clocking flight time. OP is using terms like “militarism holidays” which I’ve never heard anyone use in conversation here, ever. We have “air shows” on patriotic national holidays like Independence day, or Memorial day. At some large sporting events like the NFL Superbowl, or maybe the MLB World Series get “flyovers” over the stadium.