I found the BO1 Double Elim format really fun because every match is equally important now. You can no longer take it easy in the first game of a BO3 and then start playing seriously afterwards.
A competitive player should be used to losing many games in many ways, so I took the slow-mo game just like any other loss (unless you're in above RO8 and there's big prize money).
Pyras still work well on brawling maps like Paritan and Canyon; I'm starting to really like the nerf because it was too all-rounded for those maps.