The rationale of writing conference papers to get feedback and peer input that helps in developing papers for journals seems questionable. Is it worth writing conference papers, or is it better to aim directly at journal articles?
I presented 2 papers at an international conference in November 2013. At that time, I met 2 editors of journals, and I sent another paper to a journal. I was very thankful that it was reviewed by very responsible persons who helped me to improve the article. After that I developed more confidence to submit more papers to journals. I was also fortunate that I did not meet irresponsible people who would require me to pay for publishing. Only recently I found out that this could have happened.
"... is among the most annoying scholarly open-access publishers. It incessantly spams pretty much everyone in higher education, medicine, and research. It specializes in spamming people making presentations at conferences, timing the spam to arrive right after the presentation is completed and inviting the victim of the spam email to convert the presentation into a scholarly article for one of its many journals."