First, you can't settle the Sinai heavily, you can hardly find a less hospitable locale in the planet.
Second, the Sinai is the back door to the Suez Canal. Israel is not going to be allowed to buy it, seize it militarily or otherwise obtain it. If they try then the scenario becomes a question of what happens to Israel after the British blockade the country or, more likely, inflict a few major military defeats on the nascent state.
As for Golan, still outnumbered by the Palestinian Arabs and extremely so until the refugees from Germany begin arriving, there aren't enough Jewish settlers to waste on a French colony where they'll never be allowed to secede and where the slightest hint of such intention will probably get them expelled by the French. Not to mention 'heavily settled' would mean a tiny slice of Syria with a few thousand Jews at most, in a nation with something like 1.5 million people, so there isn't going to be any legitimate basis for separation.
Both of those places are territory that Israel controlled (quite solidly) after 1967 when it managed to dislodge Arab militaries many times it's size.
I know that the way you're wording your response you're thinking of an earlier POD, but between 1967 and the mid-70s, it would be completely logical to see an Israeli Sinai. The IDF was very much at home there after the Six Day War. It gave Israel something it had never had before: strategic depth.
Before then if there had been an attack then the Israelis would be meeting it on their doorsteps. Controlling the Sinai gave them room to maneuver, train, and soak up an invasion while preparing a counterstroke. This served them well when the Egyptians came in Army Group strength in 1973 during the Yom Kippur War.
Anwar Sadat was the man who got the Sinai back for Egypt, and he did that at the negotiating table. His thanks for that was a bullet from a Muslim radical. It's completely believable that Sadat could've been killed earlier, before the Camp David Accords which got the ball rolling on Israeli return of the Sinai to Egypt. And had he been assassinated before that, the IDF still would've been on the bank of the Suez Canal, entrenched on the successor to the Bar-Lev Line.
What piques my interest is wondering about 1982: Syrian and Israeli forces clashed again in Lebanon, both on the ground and in the air. But their was a distinct lack of will missing from the Syrians, even though they threw so many aircraft into the fray that 2 Israeli Eagle pilots became aces.
The Syrians had no willing partners left to share their hate of Israel with. All they had was the PLO, and the IDF advanced to the outskirts of Beirut in '82 to show what they thought of that. But had a militantly anti-Israeli leader/government been in power in Cairo in 1982, one that calculated the Sinai could be captured while the IDF was tied down in a guerilla conflict in Lebanon, then things could've gotten very hot very fast in the Sinai.