I would like to see mechanism to "delete all before this" or "delete all after this"

Why ?

When I am going through screenshots and am 1/2 way though and give a thumbs down, I lose my place in the shots. So might be nice to have thumbs down, and delete all prior...

Also can be a touch slow to load when have 500 - 1000 shots to be reviewed, not sure if could be grouped by 100 or something to help that.