>Problem 3: "you'll hit the 200k token limit..." ... Suggestion: use 1 million context window LLMs.
Yes, if the model someone is using only has 200k token limit, that would immediately suggest to me that it really isn't a sophisticated enough model.
Most of my coding sessions end up being about 350k tokens long when I finish, it wouldn't even fit in a 200k context. And that isn't counting the cache-reads by subagents, etc.
It's worth spending some time with the best Opus / GPT model, to at least get a sense of what the frontier is like.