I know what the devs said both that shooting a dog would be terrible and yes it is also having an AI in multiplayer would make it unbalanced...well with what I have in mind maybe won't (except for the shooting the dog part, but it might be avoided depends on the devs on how I'm proposing)

Attacker
Name: Cerberus
The dog would be attached to the operator and make noise and give away the position more easily, and when the dog smells the scent of an enemy, when it does the dog will make more noise and be able to be deployed, time to deploy 2-3 sec, and go after that specific operator, unless the dog sees a defender operator while going to the scent of another operator also the dog will go after the first scent it picked up even if there is another trail along the way, when the dog reaches a defender operator it will down them like a frost trap for duration and HP, how to escape it is for someone (attacker or defender) to kill it, has same HP as an op and can be killed instantly by a headshot, when the operator is killed (attacker or defender) the dog returns to Cerberus and can be killed along the way, how fast the dog I'd say 4 if not 5 speed.

A few things to sort out
1. If Cerberus dies and the dog survives, the dog goes after the operator who killed Cerberus, but I'd doubt that will be the case
2. While the dog is hunting someone and cerberus dies, the dog would still go after whoever it was tracking and if that operator was killed, maybe it would still help the team or just leave?

And no the dog isn't overpowered there is just one, it can be killed via headshot or body shots, and if it rushes into objective and even if the dog does get someone the dog is essentially dead, unless everyone is roaming

What do you think of this concept, the devs probably won't add a dog into the game just because it's a dog but I can still put this here for others to look at

OPERATION // RAINBOW REINFORCEMENTS

Given that Rainbow Six Siege's storyline is going in a direction of ASH vs KALI, I have adjusted 6 of my fan-made Operator proposals so that they are now part of the Pathfinder C.T.U.s. Why did I do this?

Well, NightHaven S.I.S. now has 5 Operators in the roster, with more suspected on the way. The only other C.T.U.s that have 5 are the G.I.G.N. and Spetsnaz, thanks to LION and FINKA being added back in OPERATION // CHIMERA. Given that adding one more NightHaven Operator will mean that they will have more sway than ANY of the Rainbow Six host factions, I propose that ASH will approach SIX with a proposal.

ASH wants Team Rainbow to hold its more traditional values, methods, and morals. So she will want to have more Operators that will help ground Rainbow into support of that idea. So she starts off OPERATION // RAINBOW REINFORCEMENTS, which adds 8 new Operators to the roster and brings each of the Pathfinder C.T.U.s up to 6 Operators each.

So as a fan of both watch_dogs and rainbow six seige I believe that adding Aiden as a operative to the game would be an amazing addition to our operative locker. Aiden had to be the most badass video game character I had ever had the capability of playing as and if he could be brung into this newer and more modern light it could pave a whole new path for the players experience/perception of Aiden Pearce as the badass vigilante he is. After the rockie start of the original game back in 2014 it's about time for the original game to get a face lift by bringing aiden onto the rainbow team and eventually pumping out a remastered version of the original game to look even better than the E3 demo for watch_dogs. To fix the amazing franchise of a game that Ubisoft could have ever created by working with the community to fix what problems we saw fit in the original game and improving it to make it the true next gen hacker game it really could be.
@FrankByDaylight on Twitter for this concept art