Signature campaign has always been the most rewarding way to earn a decent amount of Bitcoins. The only you would need to do is to invest your time to make quality posts and you'll be earning good profits. Trading is also a great way to earn Bitcoins, but you need to have experience in doing such task. 
Just keep in mind that you shouldn't think about earning with the signature campaign on. Instead, focus on your posts and contributing to the forum, and you will be rewarded with knowledge, experience, and happiness. Of course. I've learned a lot of things by browsing through the forums and making good quality posts. I don't do for the earnings, instead I do it to contribute to the forums and at the same time to have fun!
But hey, I guess that's that for our current generation here on bitcointalk
Why sure. I've always been active making at least 14 posts a week before joining a signature campaign. The reason that I'm very active in BCT is because I'm a huge Bitcoin fan. Ever since I got into Bitcoin, I've got fascinated by its decentralized nature. So, even if all campaigns were banned I would still contribute to this forum.