Also, some of what you describe sounds expensive. Do you find these techniques + cheaper models better than single-shot with larger models?
Yes, it can get expensive. We do something in financial markets where the cost of a single end to end task could be $100. That doesn't mean cost doesn't matter though, it matters a lot - if we screw up and it propagates, it's money down the toilet. And if we could get the task down to $20, it would make a difference.