Arteta isn't my first choice, but compared to most of the realistic possibilities he's streets ahead. He's been touted as a coach with huge potential (and a future top level manager) since before he's even qualified for his badges... He nearly got the Arsenal job 18 months ago, and since then has another year and a half working with (arguably) the best manager in the world.
Is he a guarantee of success? No (but nor is anyone else). But he has a much higher potential ceiling than most of those we seem to be in the market for.