Going to address your post a bit out of order here.
From what I hear, a high int build with the turret perk high enough they can place 2 is OP as hell.
I reckon most Tier 5 weapon skills are pretty effective. Also, 'From what I hear' suggests you don't actually have a lot of personal experience with this, yet you talk like you're an authority on it.
They can clear poi's even t5's with next to no risk as they can just place turrets and hide, or pull out a gun to kill even faster. Its the only weapon that is that safe in the game. Look at it this way, we went all this time without them and did fine, and then they were put in, now most players depend on the junk turrets to survive. That alone should tell you there is a problem with them.
So basically what you're saying is 'never innovate.' Also, how do you know 'everybody' is using them? This thread is full of people saying they either never use them or only use them situationally. Do you play a lot of multiplayer that you'd be able to see everyone using them? Or is this just more conjecture? For my part I can only speak for myself, but I don't really use them.
The A19 junk drone is going to make the problem even worse, as now you have a companion that heals you and is a mobile turret, it even has storage space you can store items in from what the dev was saying. You can probably store ammo in its storage and it'll reload using that ammo just like the player reloads a gun, or at least I'd hope thats what they do. A non-int build can probally use one too, if they loot or buy one.
More speculation. Let's not complain about things going in the game because of what they might do, yeah? We have the barest framework of a feature and you're already trying to use it to discredit current gameplay elements that are only tangentially related.
Now the main meat of things.
Using it held in hand is perfectly fine, what makes them broken is you can place them (even 2 with high int) while also weilding another weapon in your hand. Can I use 2 m60's at once? 2 smg's at once? 2 ak47's at once? no. Its the only weapon where you can essentally dual weild by placing it down and pulling out another weapon. Not to mention there is 0 delay to pick it back up, the ammo is made out of scrap iron everyone has a abundance of in the inventory. It also has a fairly high knockdown chance. The major issue is, that you don't even need a int build to use them well, you just need to find one, then you can easly cheese the game, you could clear poi's by just placing the turret down and letting it kill them, it'd take time, but its 100% safe pretty much. Also the turret can use the drum magazine mod from Machine guns, I have a t3 junk turret that has a 174ish round clip and I have 0 in int at all. Even moreso when the default difficulty for the game now is essentally "easy". On nomad, players and zombies each do 100% dmg to each other, the one below nomad which is the new default, player does 125% dmg to zombies, while zombies do 75% to the player or something close to that.
That seems more like an issue with the settings than with the turrets. On normal difficulty settings most weapons don't need to worry about knockdown chance because they just one-shot the zombie. This only gets more true as the difficulty gets lower. As for clearing POIs 100% safely, most players with any playtime in this game can do that already because
it's not very hard. I've done Tier 5 POIs on default difficulty with a wooden club and primitive bow, looting new weapons as I go. The over-reliance on and predictability of sleepers and the power of some low-level perks, especially regenerating health, renders this task 'not very difficult.' It also costs less than using scrap iron to reload a turret.
As for turrets themselves, let's have a peek. Disclaimer: I did not add in damage bonuses from mods or from the base attribute, as they are (if I remember correctly) the same across all weapons and therefore functionally irrelevant.
First, their base damage. I went into an unmodded game and grabbed a few weapons for testing. All weapons are Q5, the highest craftable level.
Turret: 15 damage, 109 rounds/min, Range 8
Pistol: 42 damage, 182 rounds/min, Range 21
M60: 58 damage, 455 rounds/'min, Range 59
So as a baseline, if we have two turrets (one held, one placed) then two junk turrets are weaker than a standard pistol (doing 15 damage at 218 rounds/min, for an average damage output of 52 DPS vs. a pistol's 42/182 = 127.4 DPS) at a range just longer than that of a pump shotgun. Considering the amount of 9mm ammo the average player is going to be drowning in if they're a busy scavenger and aren't incredibly wasteful, this is underwhelming. The M60 outright humiliates it, doing a blistering 58/455 = 440 DPS. But wait, what about with skills? Well, I'm glad you asked. Let's look at them.
Turrets at Tier 5 gain 40% damage, 120% rate of fire, and 9 range, and you can use another one.
Pistols at Tier 5 gain 50% damage and 25% rate of fire, and every third consecutive shot deals 100% more damage (which, for our purposes, will factor in as an extra 33% damage bonus).
M60s at Tier 5 gain 50% damage and 25% rate of fire. The stamina recovery isn't important for our purposes.
Modifying our previous numbers...
Turret: (15*1.4)=21 damage, (109*2.2)=239.8 rounds/min, Range 17
Pistol: (42*(1.5+1.33))=76.86 damage, (182*1.25)=227.5 rounds/min, Range 21
M60: (58*1.5)=85 damage, (455*1.25)=568.75 rounds/min, Range 59.
And now we re-do our math. Turrets now get multiplied by three (2 placed, 1 held) to get us 21 damage at a staggering 719.4 rounds/min, for 251.79 damage per second. An impressive boost! How does that compare to the pistol and the M60? Surprisingly, it's still losing to all of its counterparts. The pistol is now doing an aggregated damage of 76.86 damage at 227.5 rounds/min, which means it's doing 291.4 damage per second, and the M60? Hahahaha. The M60 is doing 805.7 damage per second. Not even a contest.
So we've established mathematically that, of the three contenders, the junk turret is the weakest. It also requires the most effort to manage, since you're juggling three turrets, two of which can't move, that all have to be reloaded periodically. This, importantly, deprives the player of their mobility - Wherever they are, they're stuck there or they have to abandon their two placed turrets. The pistol and M60 are both completely mobile by contrast. So what's the junk turret's advantage? It's cheap. But here's the other interesting thing - The higher you level them the more expensive they get since the main increase in their damage is the volume of shots. It's still cheap by comparison, of course, but it's not a non-zero cost anymore.
Something to keep in mind, eh? The numbers don't lie, turrets aren't as almighty as you seem to think they are. Yes, turrets knock targets down easily, but other weapons just kill them, and a dead enemy is better than a stunned one. Also to the point, you can't start taking bonuses to turrets until Intelligence 6, by which time you'd have level 3 of any other weapon perk. I'd say they're in line with other primary weapons.
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