It depends on who you want to read your article and where you want your influence to be felt.
If you want promotion in the academic field, I would suggest peer reviewed journals with high impact factors. Supporting newer journals who are seeking quality articles for a new readership is good as well. It sometimes may be easier to get published in a newer journal that is seeking to establish itself. A combination of both would be ideal.
However, if you want a broad readership outside the academic domain, I would recommend blogs, magazines, opinion pieces in newspapers or open access publications in your field (in addition to a few high impact journal articles).
Then of course there is the challenge of finding a way to publish in areas where you have a readership of those who think differently to you. For instance, if you're a liberal academic, writing a nuanced article for a conservative audience would be quite rewarding.