United international pressure. Sanctions. It will stop it.
Like your optimism about;
First, 'United international pressure' ... how will this be applied?
Israel has suffered this for years, no effect.
Hamas have only one card left, but they will not release all hostages as they would have nothing to deal with if they did.
Second, 'Sanctions'... against who, by whom?
Will sanctions against Hamas have any effect only to make things worse for those in Gaza?
As long as the USA supports Israel, there is no chance, even the US is now losing its ability to pressurise Israel, especially in a US Presidential Election year. Sanctions against Israel would have to include arms, this is most unlikely.
Similarly if Qatar, and in particular Iran, cannot/will not apply pressure to Hamas then the present situation especially for those in Gaza gets worse by the day
The truth is only Hamas and Israel can end this and since both 'leaderships' seem to wish mutual destruction, its difficult to see even a pause in the fighting being successful, let alone a lasting ceasefire.
However hope I am wrong and you are right.