Rob, you are unnecesarily complicating matters.

Either you can have lightning strikes in the vicinity of your antenna
or you can have a direct antenna lightning strike.

You can completely separate antenna design from the effects of
lightning. Just erect your antenna according to required radiating and
receiving properties. Inverted-L's and dipoles are simple enough.

If you expect lightning strikes in the vicinity then all you can do is
place a lighning arrestor in the coaxial feedline. Or from each of the
wires of a twin, balanced feedline down to ground. In the case of a
nearby lightning strike, this can do much to protect your radio
equipment but will not guarantee complete protection.

In the case of a direct lightning strike on the antenna there's
nothing you could have done to prevent it. Absolutely anything can
happen to your antenna, equipment, or anything else in your premises.
Including yourseslf. Just assess the extensive damage and inform your
insurance company.

On the other hand, don't completely disregard the hints and tips you
may receive from other conributors to your query on this newsgroup.
But it's all a matter of probability and chance.
----
Reg.