You said you welcome suggestions, so I am going to take you at your word. This is a good effort; it would be pretty difficult to take it to the next level.
To take it to the next step, you'd have to animate the lightning so that it actually grows during its lifetime, from a small leader into a multi-branching structure.
And if you really want to impress the audience, then you would also animate the variation in reflected glow on the nearby "bumps" (no word has really been invented for this...) in the clouds.
I've looked into the matter extensively. I intend to get the effect I'm looking using some good but inexpensive footage from pond5.com and take that as a starting point for more development.
I might also mention that there was a previous lightning freebie in the forum a couple of years ago, if I recall correctly.
Thanks again.
General Picture - animating now to life itself(tm)
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