the only thing i ever missed from Reason was the sampler (the NN-XT). one thing i like to do (and it's hopeless in the exs24); load a sample, play my track, then try OTHER samples playing the same part (i.e. a drum loop trigger, or a weird effect, or a pad, or...anything).
exploring this way with the exs is hopeless. being able to try out sounds WITHOUT having to commit to anything...miss that.