Like they say above, don't really think donor or posts really should make someone seem more trustworthy, but with vouches is the best.
Thing is, each person is going to judge how they trust you, I have trouble trusting people who have 60+ vouches. Just because they haven't scammed others doesn't mean they wont' scam you. I have been scammed by a guru with donor, and good amount of vouches back in the day.
However, until you get someone to go first for you, people aren't gonna really see the trust in you. Even though I have three vouches, all it means is that I have traded and it has gone smoothly, but despite that I went first each time, so people aren't going to automatically be oh hey! I can trust him.