Vogelbird is a bit extreme, owning probably half of the checker tags.
It's likely we will adjust how much points different things will reward. The plan was to do it this year, but we haven't gotten down to it yet. It's something we have to review and analyze first.
The things that should give the most points is where we need the help. That might very well be the QA forum in the future.
To give some numbers, vogelbird has around 100 QA forum support points and ~500 points from checker scripts and tags. We never predicted that someone (one user) would make such big effort with the checkers. We (and the community) are very thankful though.
Since the site is getting more and more popular (more users), it's getting harder to get the PGC Diamond badge. We may very well increase the number of users who gets rewarded with it. Currently it's the top 30, and then top 100 (31-100) gets Emerald.