The Line gun is great for taking out two limbs at a time on the weaker necromorphs.I might be talking about the Line Gun instead of the Force Gun actually. But it seemed powerful enough to blow limbs off from a distance. I use the flamethrower for the little crawly things too because itd be tedious trying to hit those with individual shots instead of blanket fire, and plasma cutter to save on ammo for the ones i love to use the most, but i do wind up using all guns because i burn through my ammo cause ill be startled by a necromorph and just start unloading in all directions lol.
Funnily enough apart from the Contact beam which was good against the wall monsters I didnt really use much of the secondary fire options on most of the weapons. Only time was where I panicked and managed to launch a Line gun lazer trap at the Hunter and it stuck to its leg. So then I had an unkillable monster with lazers shooting out of its kneecaps chasing me around, and I actually died laughing.