Any subsequent government isn't likely to be a friend of Israel, either. They might decide to stop actively funding attacks and put the money to better use, but I wouldn't be so sure of that. It's the basis of a lot of ally relationships that they will want to maintain.
Iran had good relations with Israel prior to 1979 and never persecuted or expelled its Jews after 1948 unlike every other country in the region. In fact there’s a great degree of very old cultural affinity between Persians and Jews. A secular Iran is likely to have very close ties with Israel if for no other reason than as a backlash to the excesses of the cleracy.
I agree, we don’t know what comes after bad leadership. Maybe a worse one.
I’m afraid there isn’t much worse than a leadership that openly states that Israel should be destroyed, while developing a nuclear program.
Maybe a similar but more competent leadership is worse.
Why? a non-religious Iran would have difficulty maintaining alliances with islamist organizations such as PMF and Hezbollah that were used to slaughter Iranian protestors. Also, like Syria it would probably pivot to a US-led alliance
