The rough criteria I have concerning requests for more tools and/or responsibilities:
- The editor is knowledgeable in policy/process;
- is active in such discussions;
- is responsible in such discussions;
- is active (and responsible) throughout other talk pages;
- is civil/agf/eq (and someone who I don't think needs the bluelinks to know those shortcuts, by now) even in the face of some of the more challenging situations. The last is a big clincher for me.
The question of how one will determine consensus is, for me, a question of thought process. Anyone can count "votes" - can one read for content?
It's a question of whether I think you can. If I'd trust you to make such decisions, and to use such extra tools responsibly.