Whether it's premature or not, I'm just putting the idea out there. The question is, what does that take away? If the item is truly flagworthy, then it shouldn't be any problem filling in a box.

The added benefit is that you have much less accidental flagging.

all barriers to doing something do, in fact, matter. the more barriers, the less people will use the flag.

just like any tiny barrier to signing up for your website is important.