Kind of just sounds like people are bad at using Maggie.
The drill is not supposed to be used directly at players. It's perfect for forcing players out of small cover, stopping healers, blocking doorways, harrasing people in buildings. And ofc you need too know where players are, but how hard is that?
The ball is not just for Speed boost.
It breaks doors, stuns, tags, and sends people flying.
You can delay enemy's pushing.
You can bounce enemy's out of cover or even off the map.
You can tag people in smoke because it's got a big hitbox, then you lock into their outline (her passive)
Her speed boost with shotgun is handy in cqc and when popping in and out of cover.
I think she is solid and versatile, you just need to think fast and understand the abilities. But I won't say no to any buffs. If you want her to become one of the most picked you just need to give her wraiths hitbox.