I didn’t really pay much attention to her major perks much. I picked the one that extends her ult duration which is actually great for those times you copy a tank like Zarya for example. But the other one that gives more sticky bombs is pretty nuts. So the perk says it gives you 50% more stickies (so 9 instead of 6) but they each deal 15% less dmg. Currently landing all 6 does 180dmg. With this perk if you land all 9 you deal 236 dmg 
. Granted it can be harder to land more projectiles but if you do…then Echo turns into an absolute tank buster. If you land all 9 on a squishy they get deleted.
This actually changes some key breakpoints. With normal squishies if you land a primary and all stickies you typically have to follow up with beam or another primary. With the buffed stickies you can land all 9 with a primary fire for the kill. No beam follow up needed. The amount of dmg you can do in a game with this perk is pretty insane especially on the tank busting side of things. You can flank a support and nuke them out of existence 
. Not sure if this is healthy for the game but I’m having fun hehe
oh and btw all this is without a mercy blue beam 