Methinks you misinterpret the events -- Ben Gurion was concerned over Irgun trying to keep a separate power base within the state and the army, not about tactics and politics. Indeed he too wanted the weapons and the circumventing of the UN observers.

On the general point, while there were differences between diferent factions of Zionism, it was not about ethnic cleansing and such. This is from Ben Gurion:

"Zionism is a transfer of the Jews. Regarding the transfer of the Arabs this is much easier than any other transfer. There are Arab states in the vicinity [...]  and it is clear that if the Arabs are removed this will improve their condition and not the contrary."

He was pretty clear about what he wants a decade before the war -- in a letter to his son:

"We must expel Arabs and take their places [...] and, if we have to use force - not to dispossess the Arabs of the Negev and Transjordan, but to guarantee our own right to settle in those places - then we have force at our disposal."

There are truckloads of quotes on the web with Ben Gurion's practical considerations about how to bring about this "transfer" during the war. But I will quote on another issue, the ruthlessness of tactics:

"We adopt the system of aggressive defense; with every Arab attack we must respond with a decisive blow: the destruction of the place or the expulsion of the residents along with the seizure of the place."

Ben Gurion is no exception in the Zionist Socialist camp. The fascistoid hijacking of leftist movements Migeru mentioned happened in the early 20th century. Here is David HaCohen, trade unionist and later Labour MP:

"I had to fight my friends on the issue of Jewish socialism, to defend the fact that I would not accept Arabs in my trade union, the Histadrut; to defend preaching to housewives that they not buy at Arab stores; to prevent Arab workers from getting jobs there... To pour kerosene on Arab tomatoes, to attack Jewish housewives in the markets and smash the Arab eggs they had bought; to praise to the skies the Keren Kayemet that sent Hankin to Beirut to buy land from absentee effendi (landowners) and to throw the fellahin (peasant farmers) off the land - to buy dozens of dunams - from an Arab is permitted, but sell, God forbid, one Jewish dunam to an Arab is prohibited; to take Rothschild, the incarnation of capitalism, as a socialist and to name him the "benefactor"-to do all that was not easy."

Even the rosy picture you paint of the very first Zionists's views of living together with the Palestinian Arabs was in reality a bit different -- part White Man's Burden, part ethnic cleansing the nice way, as Theodor Herzl in 1895:

"When we occupy the land, we shall bring immediate benefits to the state that receives us.  We must expropriate gently the private property on the estates assigned to us.

We shall try to spirit the penniless population across the border by procuring employment for it in the transit countries, while denying it any employment in our own country.

The property owners will come over to our side.  Both the process of expropriation and the removal of the poor must be carried out discreetly and circumspectly."