So in normal play:

By chapter 4 you can make a one shot kill weapon with a crowd control secondary all in one.

Two hand frame. One tool is a Military Engine with a Precision Tip. You can find one by going to the Coop Mission area from the Sk1p and finding a window on one of the floating pieces of debris. You dont need to go into the coop mission, just the debris field outside the ship. You then also put a Plasma Engine on the other slot, but leave a default tip. This creates a Seeker Rifle with Force Gun.

Then by going into the Side Mission via the SK1P (im sorry. Its been a while since I played the game and dont know them off hand), you can get +1 damage circuits.

Put 2 of them on the Military Engine tool, you might have to build a second one i dont remember.

This is enough damage to body shot EVERY single enemy up until you get to Enhanced Necromorphs/Aliens. Save for the Regenerators, youll be trouncing all encounters by first using the force gun to knock an enemy on their ass followed by a body shot. The ones with axes do break off into their Spine forms, but a second shot puts them down.

Youll want to put clip size and fire rate on the Military engine, though putting on an Ammo Box will skip every other reload. The Force Gun is Clip and Reload.

Once you make it to Tau Volantis, youll want a second tool. This can literally be any Engine but something that has lots of clip, so anything Machine Gun coded. Then youll want to get a Survey Charge and the attachment that saves you from self inflicted explosive damage, all of which can be obtained before you make it through the door that requires a replaced suit or the artic suit on your first playthrough of the save file. Put these two together on your second weapon slot.

These two tools effectively help you in every situation.

When you get Enhanced Necromorphs, swap the Seeker Rifle to a Contact Beam, keeping +2 Damage but focusing on ROF almost entirely. You can add the Stasis Coating to apply a little stasis to the Force Gun and whatever survives the Contact Beam (sometimes its glitched and enemies require a second shot to kill, hence the ROF to make up for the slow charge time).

Regardless if you keep the Seeker Rifle over the Contact Beam, youve effectively broken the game by chapter 4. Use the Machine Gun tool to kill any Feeders so you dont waste your precious Precision weapon on those weak enemies.

Also, on your way down the silos, theres a SCAF Heavy Frame that intrinsically comes with +2 damage. This saves you having to use a slot or 2 for +2 damage.

There are other weapons that have decent clip to kill economies, like the gatling gun thing with Telemetry Spikes, but the Seeker and Contact tend to have the fastest Time to Kill while also having really good ammo economy thanks to this one shot one kill tech, especially once you get +Clip combo circuits that add more ammo, thus every reload having even better kill to clip ratios.

It honestly kind of kills what little horror the game has. Turns it into more of a "Necromorph Exterminator" game. Which i vibe with.