Did the Shah also order that virgins be raped before they are executed so they don't go to heaven, or is this equivalence entirely false?

The situation with the Shah is somewhat similar to the situation around the English Civil War in the 17th century.

The King was authoritarian, but also a bohemian. The Roundheads were religious fanatics. They succeeded in overthrowing the Crown and executing the King, but they also turned out to be insufferably religious. After Cromwell died, the population re-invited the deposed monarch's son back, under some conditions. He met those conditions; his successor did not, but was promptly thrown out into exile, because he wasn't able to consolidate enough power anymore.

Unfortunately the Iranian population wasn't able to reconsider their choice after Khomeini's death (1989), because the government was much stronger and much more willing to kill. Also because of the Iraq-Iran war.

Nothing says legitimacy like having to shoot people en masse in the street

I don't think half the Iranian population support's the regime. Can you share the evidence for this claim?

I highly doubt that in Iran half the population supports the government. If you hear Iranians it's more like 5%. Even if it's really double that, that's still only 10%.

Plus after wars the mullahs wanted that ended in total disaster and enormous numbers of casualties (given that the central promise of islam, of allah if you will, is military success), whilst the mullahs never had real support of the Iranian army, there are now reports of a lot of individual soldiers and even one or two of entire units attacking mullahs and religious schools, killing teachers and students. Oh, and after the recent "success" against Israel, the mullahs once again cut military pensions, with now reports they just stopped paying entirely. Given that it's the military doing the planes, one wonders that if the "supreme leader" runs to a plane if he'd make it on board the plane without a bullet. The government only has the basiji, the "religious army" (technically their name means mobilization of the oppressed, a reference to Marxism, and to who brought the mullahs to power. Of course in practice the basiji is anything but what their name implies, they are the oppressors).

then lets talk about Palestine, and the people commiting a genocide there, planning to "liberate" Iran useing the same methods

many of the people protesting the exectution of Renee Good, are carrying Palastinian, and Irainian flags, as they know the same people are behind ALL of our troubles.