Seven Deadly Sins... with a twist.
You know how Gluttony is always represented with a fat guy or Lust with a prostitute? I find that extremely lazy and boring. Wouldn’t it be more interesting to have a prostitute represent Sloth, as she is unwilling to learn any skill whatsoever (and which would ultimately lead to her undoing?)
Write one (or seven, if you wanna start a series) story about a deadly sin presented in an unexpected or unusual manner, Stay as far away from stereotypes as possible and most of all, the sinner must be the architect of their own demise.