Why did Bioware do so little with the Yagh?

Yes.

Made more apparent in that the yagh literally have no meaningful involvement in the trilogy outside the Broker and that one loose yagh that disappears the second it breaks out.

Yeah I think it was just used to give us a unique boss to battle against. Especially as they gave a bit of a throwaway joke to the whole situation in ME3 during the Surkesh mission.

I agree.

I feel like they didn't because, in ME1 at least, there was a whole big thing on "Who is the Shadowbroker?" If I remember correctly, even Liara in ME3 is super vague about the events of the DLC.

Didn't the t'soni asari cry like a baby after one was killed? Maybe in the next ME game, Bioware will give her a yagh as pet to make her feel better.

They would have been the best threats after the reapers. Maybe even introduce the Raloi and Virtual Aliens as well. The latter two could be pissed off or waiting to pick the bones of the current council races after they've been stretched to the limit post reapers. It would be far more compelling than Andromeda.

It's not just you.

So, you're asking why BioWare didn't do more with the Yagh in a hypothetical ME4 that never came out?

Yeah, stumped on that one...

Iffy nature of this idea aside, something similar in spirit wouldn't have been a bad sequel. Imagine if standard MW tech (mass effect tech) crashed on Parnack. How long before they knew how to build their own, given their intellect? Clearly, resources would likely be a huge obstacle.

Now, swap the Yahg and Parnack for some unknown world and unknown species. Maybe this species has feasible access to enough resources to get started. Not every threat needs to be as crazy as the Reapers. Accidentally handing advanced tech to the wrong species could start the next Rachnii War, in a manner of speaking. In another of Dutch's threads, I just posted my old idea for what the "next ME game" could've been, pre-Andromeda. I think having a new MW threat arise would've been better than going intergalactic, and there are plenty of ways it could be done.

The yahg? Probably not. Someone just as scary? Sounds fun.

I think it is more likely that the Krogan are made out to be the bad guys. In a weakened Milky Way Galaxy, the guy with the biggest stick will get ideas, and with the Krogan believing that the genophage is cured (whether true or not) they are going to A ) Want Retribution and B ) Want more worlds to inhabit. That means they will go to war, and in a weakened Milky Way, they would probably win, because after the implied moral ambiguity of the genophage, no one is going to risk completely wiping them out and being the bad guys themselves.

There's also the Batarian Survivors, who are also likely to take to arms to ensure their survival. The Milky Way is going to get a lot more unstable post-war than during the war. No matter how ME3 ended, the Galaxy IS going to go through a period of chaos and uncertainty. We're likely to see a lot of lawless anarchist worlds or Omegas cropping up, merc bands will also become a more common form of employment, the Galaxy will not quickly recover from this threat.

I'm not even sure I'd like to see what the state of a post-war Galaxy is. It's not going to be pretty at any rate.

I want to see some oravores. Maybe an entire enemy faction in cryo sleep wakes. The yahg would be interesting. I think the Yahg would be a worthy future foe in the Milky Way, I just doubt ME4 will ever happen (maybe if they set it 50 years or more past the OT). Those black ark collectors would be cool to face in SP and not just MP.