I still don't find Glory useful enough on Hard and beyond. Her to hit chances are abysmal. Not even additional AP makes up for that.
Then again, the game follows some strange progression pattern. For about 60% of the game your companions can't hit the broad side of the barn. Then, at the very end when you get them all to 6th level, their to hit rate skyrockets. You see 90+% chances all the time. Don't know if it is their skills that got upgraded, or if it is the enemies that are lacking.
Eiger wasn't too great until the very lategame. Then she became death incarnate with that shotgun in burst mode. Two shotguns, actually. I found reloading to be a hassle.
Anyway, I could not justify having Glory in my party. With Dietfried and his Earth Elemental I never really lacked the ability to dish out melee damage and stun enemies in key fights. It did not help that I almost never really needed to use medkits in the first place, yet I found 1 AP grenades extremely handy.