On the curation guilds, I recently was approached to become a part of the Steem Guild team focusing on photography, along with another user who I suggested (and who was actually already on their list of potentials). I think I was chosen because like you said, I already do what I can to support and spread whatever value I can within my area of interest which is mostly photography.

So I think you'll find that members of the curation guilds are people who naturally do it anyway, but have been hooked up with some power behind us which makes our curation a bit more valuable.