There are two envelopes. The outer envelope has your name on it, you sign that and return it. You can mail it in if you like, or drop it at special drop boxes around town (I always do this because I'm prone to waiting to the last minute.)

The inner envelope is anonymous. They verify the outer envelope and open it, then pass the inner envelope to a separate area/volunteers to do the counting.

The contents of the voter guide are submitted by the candidates. For ballot measures, pro- and con- statements are submitted by sponsors or members of the public. I don't have mine handy but I think they actually print several pro/con statements for each.

I'm not sure how unique this is but ballot measures actually have brief statements printed on the ballot explaining what they will actually do, preventing issues where you're like "wait should I vote yes or no on this if I want this thing banned?"

> A YES vote will: Instruct the legislature to write a law preventing future taxes on groceries. A NO vote will: not send any recommendation to the legislature.

Yeah, I moved to Oregon recently and found the ballot structure to be pretty good.

It outlines the different propositions, explains what happens for a yes or no vote and then has multiple pages devoted to showing arguments for and against mailed in by concerned citizens and organizations.

Parties are allowed to enter their own party descriptions. I haven't read the sections on candidates yet