On the adding tags issue. I say it's ok how it is. You either make your own tags, and risk under tagging or tagging things wrong, and get reported (this is the part that really depends on the community) or you let others tag pictures for you, taking the risk of OTHERS tagging your picture wrong (again, depends on the community). Tagging can be, and will be abused no matter the system it works by. Because the flaw isn't in the tagging system.
Also, some better "education" on tagging could really help. I'm sure I'm not the only one who has no real idea how to tag a picture properly or right. And the "Tags and you" article only seemed to make me realise I tag even worse than I thought.