F-111s and E-3s for one
Doubling his F-14 order and funding a "B" model?
What the Shah had planned:
70 more F-14s (although I've also heard F-15s or Mirage 4000, but more F-14s makes the most sense). I doubt he would have funded an engine, but they would have been upgraded with F-110s later in the 80s.
300 F-16s. F-5s and possibly F-4s would have been sold on to others, like the F-5As were when he bought F-5Es.
4 Kidds.
1500 "Challenger 1". The UK ended up with Challenger kind of like the U.S. ended up with the Kidds.
F-111 was out or production, so that's a bit of a non-starter. E-3 had been rejected, but since they got approved for Saudi, they may have been approved for Iran later.
Iran-Iraq war would not have happened. Saddam was taking advantage of the confusion and chaos of the revolution. He wouldn't have tried if the Iranian military wasn't in upheaval. Same for Kuwait later. That was what the U.S. support for Iran was meant to prevent.
Continued cooperation with Israel. I can see Lavi going forward with Iranian cooperation.
The two big questions to me are what would have happened after the Shah died and would the economy have diversified? Best case would be political liberalization along the lines of a European style constitutional monarchy and economic diversification away from resource extraction towards industrial production.
Post Cold-War and there are just too many butterflies. I can see them turning into South Korea as well as remaining an autocratic petro-state.
Sure, they were so fed up with the Shah that they ranked islamists and communists as "preferable options" - or maybe they hoped they would neutralize each others.
Brilliant thinking, really...
It was a broad-based revolution, with strong support from moderates, but as can happen following a revolution the faction that is the most murderous kills the moderates and takes over. See France, 1789, and Russia, 1917, for the same phenomenon.