Website monitoring online censorship in China - what's holding us back?

[GreatFire.org]

We run https://greatfire.org, a non-profit website which lets you test if a website or keyword is blocked or otherwise censored in China. There are a number of websites that nominally offer this service, and many of them rank better than us in Google. However, we believe this is unfortunate since their testing methods are inaccurate and/or not transparent. More about that further down*.

We started GreatFire in February, 2011 as a reaction to ever more pervasive online censorship in China (where we are based). Due to the controversy of the project and the political situation here, we've had to remain anonymous. Still, we've been able to reach out to other websites and to users. We currently have around 3000 visits per month out of which about 1000 are from organic search.

However, SEO has been a headache for us from the start. There are many challenges in running this project and our team is small (and not making any money from this). Those users that do find us on relevant keywords seem to be happy since they spend a long time on the website. Examples:

websites blocked in china: 6 minutes+
great firewall of china test: 8 minutes+

So, here are some SEO questions related to GreatFire.org. If you can give us advice it would be greatly appreciated and you would truly help us in our mission to bring transparency and spread awareness of online censorship in China:

1. Each URL tested in our database has its own page. Our database contains 25000 URLs (and growing). We have previously been advised that one SEO problem is that we appear to have a lot of duplicate data, since the individual URL pages are very similar. Because of this, we've added automatic tags to most pages. We then exclude certain pages from this rule that are considered high-priority, such as domains ranked highly by Alexa and keywords that are blocked. Is this a good approach? Do you think the duplicate content factor is still holding us back? Can we improve?
2. Some of our pages have meta descriptions, but most don't. Should we add them on URL pages? They would be set to a certain pattern which again might make them look very similar and could cause the duplicate content warning to go off. Suggestions?
3. Many of the users that find us in Google search for keywords that aren't relevant to what we offer, such as "https.facebook.com" and lots of variations of that. Obviously, they leave the website quickly. This means that the average time that people coming from Google are spending on our website is quite low (2 minutes) and the bounce rate quite high (68%). Can we or should we do something to discourage being found on non-relevant keywords?
4. Are there any other technical problems you can see that are holding our SEO back?

Thank you very much!

*Competitors ranking higher searching for "test great firewall china":

1. http://www.greatfirewallofchina.org. They are only a frontend website for this service: http://www.viewdns.info/chinesefirewall. ViewDNS only checks for DNS records which is one of three major methods to block websites. So many websites and keywords that are not DNS poisoned, but are blocked by IP or by keyword, will be specified as available, when in fact they are blocked. Our system uses actual test locations inside China to try to download the URL to be tested and checks for different types of censorship.

2. http://www.websitepulse.com/help/testtools.china-test.html. This is a better service in that they seem to do actual testing from inside China. However, they only display partial results, they do not explain test results and they do not offer historic data on whether the URL was blocked in the past. We do all of that.