First of all, I want you to know that the reason Grim's pick rate is low right now is not because his primary gadget is underpowered, it's simply because he's not fun.
So just adding a 1.5 scope to Grim's 552 COMMANDO will make it the operator of choice for more people.
Currently Grim's primary gadget, if fired, can 'unconditionally' find out the location of an enemy within range unless it is intercepted by ADS/MAG-NET, which is really OP. So Grim's primary gadget needs to be changed to be destructible when attached to a wall/floor after being fired from the launcher.

This robot is designed to act as part of the "react" force censoring high traffic areas that with relatively high risk, it is a 90kg or 200-pound fierce machine, but not overly big, it is dense and quite capable to hide, with unparalleled power of burst, it is programmed to tackle high risk target immediately without the target’s safety being the first concern, it can even bite on a vehicle and slows it down.
Here is how it works in game:
Op takes out a heavy control panel with a laser indicator, points at a position and right click to confirm, the good boy will be there, a second after arrival, dog is ready to pounce, the radius is about that it can hide on a side of a double door, the entrance is then completely locked (but for only one opponent), the moment an opponent is in the range and enough exposure to the dog’s line of sight, an op is immediately tackled down into basically frost-trapped situation, dog “unleashed” and the master is out of its gadget mode, dog can even swoop out a window and put opponent into that enhanced DBNO state as the result of a split second exposure to the predator. Dog has to be removed before the tackled can be revived. Robot boi has 100hp for bullets, but explosives and melee deal lethal damage to it, similar to frost mats. If the robodog is killed, boi will come back after 30s, as long as the master is still alive.
when the dog-master op is further away from the dog over 10m, or when the tackled opponent killed, or the master cancels his gadget mode, the dog will quickly go back to the master’s position and basically disappear.
This is a gadget for ambush or entrance denial, the entrance is denied to the degree that if the dog is facing a window, an attacker can’t expose himself to the window at close range without being almost taken out of the round in the blink of an eye (well, given defender aggression and just peek everything kind of a default for Siege, robodog attack is pretty much a milder scenario in favor of defense strategy). For attackers, once they have solid information, they can organize attack without the master able to shoot back immediately, if the robodog is not blocking the way and thus must be removed, when the master has second thought and calls off the dog attack, your own boi will track you down, giving away the position of the master, this, the price of love on the ruthless battlefield.

Is there any chance that we'll see the old, pre-Y5S1 recruit come back to the game? I really miss the guy still. Part of me hopes that, if they do bring old Recruit back, that he'll have all the guns in the game, but he didn't even have them back then, so I doubt he would if he came back now. (Besides, all the guns would be overwhelming to newer players.