I don't know anything about websites so I have no idea how hard it would be to implement something like this but it definitely would be nice to have https://e621.net/iqdb_queries somewhere into https://e621.net/uploads/new as hyperlink or even incorporated as a whole. It's not having to find it (and only way I know it's through already posted image) and open is too hard but as I said it's just for ease and comfort.
So just my few cents.
Cheers.