I dunno, the tropes that tend to get lifted are diverse enough and varied enough that it works well, particularly if you've got a DJ who knows how to build a set rather than just playing every juke influenced tune he can get his hands on or every housey tune or whatever.
I mean, the worst you can say about a good set in this kind of style is that it 'just' mashes together the best bits from a wide range of other stuff - grime strings, MCs, garage rhythms, funky rhythms, juke vocal samples, R&B vocals, dubstep bass, detroit strings etc etc etc. Which is true of early IDM as well, and is also more or less verbatim what Simon Reynolds said about UKG when it came out. Make of that what you will.
Genuine question here, though, not rhetorical - can anyone name any more-or-less new tropes that have come out of this scene?