My answer, as a (liberal) Zionist Jew, to the first problem might surprise you: I would say no, I won't bomb the Hamas leader in either instance. But, let's change it slightly: suppose I must bomb one or the other. In that case I would bomb the latter, the hostages.

Why?

Because what am I trying to accomplish here? Destabilize Hamas? Will killing a leader do that? It might, depending on who the leader is, & if there isn't a roomful of subalterns reader to take his place.

Or is it revenge?

Either way, if I am forced to launch the missile I prefer to launch it in such a way that the consequence won't aggrieve & enrage a new generation of Hamas (or similar) fighters & planners. Hence the cold calculus of preferring Jewish casualties (in this particular context).

I'm not sure what to make of the second example. What it proves. I would have greatly preferred that Israel, in the wake of Oct 7, proceed with the Saudi accords while enacting a program to assassinate Hamas's leadership, especially those who live abroad. Even such a targeted operation, however, is bound to incur civilian casualties. It is war, after all. And civilian casualties always appear on the butcher's bill. To claim otherwise is to lie to ourselves.