quick comment because I just found this page flipping through – I have each of the sites that you have mentioned…. and also smug mug (which I use as a portfolio of my “art”) I got that before I ran across 500px and my 500 px is empty, because like you, I am intimidated by the level of talent running there and know I’m not as skilled as most of the folks there. One site you did not mention that I use extensively is photo bucket. Flickr spanked my hand early ON (2004) for posting photos that were not my own – they were photos that i had collected from magazines over the years that i wanted to share, mostly of celebrities. Flickr frowned upon that then, although, these days I see some users that almost solely post work that is not their own – one in particular I warned years ago and they are still there posting thousands of old magazine model photos (and protecting them from pinning etc, i might add, ironically). Photobucket doesn’t not police in that way, although, they do NOT like nudity ( a barebottomed photo i posted was flagged and deleted). there are editing tools there and decent organization and privacy settings.