This. This is what they’ve done.
She has three attacks: a tri-shot finger pow that chips away at health, a more focused beam that does high damage to weakened enemies, and a sticky grenade. The sticky gloop will do a considerable amount of damage, and comboing it with any of her other attacks will leave an enemy or two begging to be healed. In conjunction with her boost and glide manoeuvre, she’s a flanker’s dream. There are certain spots on maps that Echo can simply glide over, meaning you can take out inattentive snipers by forgoing the usual paths to them. She’s also great for making a mad dash at a cart during overtime. Most controversially, her ultimate means she can clone into a player from the enemy team and build up to that character’s ultimate super quickly. There are fewer downsides than almost every other ultimate in the game. When she hits it she has the cloned player’s full health, and when she dies in that form she returns to her own body with full health. As someone who rails against the myriad ways that Overwatch enables players to speedily return to health, this is the most egregious example going! A weakened Echo can turn into a 600hp tank and then return to 200hp when she’s “killed”. Admittedly, it’s a far more limited power than a simple health boost, but it feels futile to attack her when she’s rampaging around as another player. She won’t die.
But… my short time playing as her last night was lots of fun, especially when I worked out my own personal meta: glide up and over, sticky bomb people from behind, then fire whatever else I have left. I died a lot, but I also took out a sniper nest a bunch of times. She’ll be nerfed. She has to be. So, enjoy her superpowers while they last.