I think the list for mentors looks long and somehow deterring. We might be driving away perfectly good mentors?
What really matters is that mentors are available and willing to help newcomers landing, finding new tasks, reviewing their code, and basically becoming Wikimedia developers, knowing that this takes time and patience... that pays off.
We could also spell not only the duties, also the benefits. What is there for me as a mentor? Becoming a successful mentor not only should bring occasional and long term contributors to their projects, it will also contribute to their own path as Wikimedia developers, senior free software developers. Featured Projects will be promoted in all our developer events, and their mentors will have more chances to receive scholarships to participate in these events. Involvement in GSoC and Outreachy also increase travel opportunities to events inside and outside the Wikimedia movement. And, well, if they ever think of requesting a grant, having a public track as a successful mentor of a Featured Project will definitely help.