Something I've thought about before, separate from the issue you're talking about, is that I'd like there to be a way to say something on top of the re-steem.
Like, if a friend of yours posts for the first time, it would be nice to be able to say "hey guys, this is my friend blahblah, new to steemit if you want to show some love", rather than like it's just randomly re-steemed by you.
And incidentally it would help the situation you're talking about; you could edit it saying that you learned it's a fake account, so at least your disclaimer is there forever too.
I've also considered that I don't like the clutter that re-steems create. I don't blog especially often, so a link to my blog would quickly not really be my blog anymore if I used the re-steem regularly.
So personally love the idea of a separate tab, or disappearing.
The blowback tho, I guess, is that now everybody re-steems loosely. Maybe it's good to make us really mean it when we want to re-steem. Not sure.
That would make a lot more sense if you could add a comment with the re-steem, it would add so many options.
Personally, I think having them be temporary or otherwise able to be removed is going to be really important in the long run.