"Habits" rarely get carried into our dreams, therefore, trying to develop the habit of RCing, self-reflection and so on is probably the biggest waste of time one can possibly think of. :p

As for using a timer, I feel it may make it more difficult for one to fall asleep. The SSILD cycles are meant to be performed in a very leisurely fashion and they need not to be precise. You should feel comfortable doing them, whether fast or slow. The 30 second rule is only meant as a general guideline. The truth is, it doesn't matter. If focusing on one sense feels particularly difficult then just skip it. On the other hand, if it feels particularly good then just stay with it a little longer. The same "stay comfortable" rule applies to other aspects as well -- if it itches, just scratch it. If you want to roll, just roll... SSILD is very forgiving.

Hope this helps!