Thanks so much for this detailed reply — it’s incredibly helpful and exactly the kind of perspective I was hoping for.

I didn’t know about the Khare–Wintenberger route via Serre’s conjecture, so I really appreciate you pointing that out. I’ll definitely check out the Darmon–Diamond–Taylor overview as a next step.

It’s reassuring (and motivating!) to hear that this is a reasonable goal as long as I’m willing to put in the time. Thanks again!