Sorry, but any analysis that suggests that Iman Shumpert is a better PG than Baron Davis pretty much ruins your credibility right off the bat. Have you actually watched him play point guard? Going into last night, his PER as a PG was a whopping 2.2. For reference, Davis's career PER is 18.0, and last year, despite your detailed and insightful analysis, after he was traded to Cleveland he averaged 19.7 points and 8.7 assists per 36 minutes. Even before the trade, he was averaging 15.7 and 8.5 per 36, which compared to his career averages of 17.1 and 7.6 doesn't feel like a "huge digression" to me.
Meanwhile, as a shooting guard, Shumpert's PER is 25.6. That means that Baron Davis can be terrible, and the move of Shumpert from PG to SG still will present a substantial upgrade to the Knicks starting lineup.
I'm with Abbey on this. This team needs a point guard, and making judgments on the feasibility of the Carmelo-Amare pairing based on a 13 game sample size in a shortened season with a short training camp before their best 5 has played a single minute together isn't particularly productive. Are the Knicks a great team? Nope. But I'm confident they'll be better than they are playing now. If their offense can perform at even a league average level, they'll win a lot of the games they've been losing recently.