Are those real peoples' photos? I know this is intended for mockups and placeholders, but the absence of any licensing info would still give me a little pause before trying this for anything but a personal project. (I recognize the 'fake logos' from logoipsum.com, they don't require attribution but you miiiiight be on the wrong side of the line of their "as long as you don't use the logo to make similar website as Logoipsum then it's all good" thing.)

I hate to be the copyright party pooper, but this is a nifty idea; a quick note at the bottom confirming sourcing and that everything's openly usable would probably encourage more people to make use of it!