Alright, if Ben-Gurion is assassinated in 1949, Moshe Sharett is most likely to become PM (he was the #2 man in the Mapai electoral list). While Israel is going to be reeling from the loss of Ben-Gurion (who most likely will be mythologized as the father of the country alongside Theodor Herzl's status as father of Zionism), Israel is going to remain stable. Mapai, the Labor-Zionist party that dominated Israeli politics until 1977, had a very stable leadership structure. You're going to see people, including Sharett, like Golda Meir, Levi Eshkol, Moshe Dayan, Pinhas Lavon, Teddy Kollek, Abba Eban, Shimon Peres, etc coming to power sooner (especially the leaders from the Third Aliyah, since they thought that Ben-Gurion was trying to cultivate a new generation of leaders without giving them the chance to govern). The reparations agreement between Israel and Germany is most likely going to come around as in OTL, though I'd expect people like Moshe Sharett and members of the Third Aliyah to have more prominence during negotiations.
Eliezer Kaplan (#3) and David Remez (#4) both die in the early 1950s, but they may end up having a more prominent role in the Israeli government. Same with Yosef Sprinzak (#5). Without Ben-Gurion, you may see the Lavon Affair butterflied away and Pinhas Lavon may end up having a more prominent role in any future Israeli government (which, ironically, may end up helping help relations between Jews and Arabs). Lavon, as Minister for Defense, extended the draft to Arab-Israelis in 1954 with PM Sharett's blessing and was surprised by Arab-Israeli enlistment. The Lavon Affair ended his career, brought Ben-Gurion back as Minister of Defense and PM, and ended the Arab-Israeli draft extension.
It can't be understated just how influential David Ben-Gurion was. I could easily see Herut and General Zionists gaining seats through new Mapai leadership mismanagement, but Herut is not likely to lead a government (Israel's electoral system requires any government to form a coalition government, and Israel was very socialist-dominated until Likud took power in the 1977 elections).