Random chit-chat with other members is best conducted either in Other Chat's Daily Chit-Chat thread (but you have to try to stay on the current topic, unless it's been dead for several hours), or in visitor messages, which I see you seem to be doing with Master Herbalist. If you have a question as to the rules about Challenges, ask Sydian, since Sydian knows what they're looking for.
As for why the Trading Corner and Competitive Battling Center aren't under the same section, here's why: there is a program that people can install on their computers to build teams and face off against each other that is called Pokemon Online. Pokemon Online has a decent following here. With Pokemon Online, you don't need one of the games, you don't need to change your wireless security from WPA to WEP, and you don't have to spend a ton of time raising the Pokemon. It's a more accessible means of battling people.