I would definitely say yes because it would bring more stability to Israel and would also make it easier for a party to be kicked out if enough voters think they are doing a bad choice.
Those are kind of contradictory.
A country shouldn't care about stability in it's electoral system, it should care about democracy and FPTP is not democratic.
Nope the reason is the incumbent/establishment party usually can count of a bloc of 20%-25% of support at the worst and in a proportional system due to their being so many different opposition parties that amount would give them the best chance out of all the parties to put together a coalition goverment.
But in FPTP even if you get 30%(instead of say 20-25% )of the vote your party is going to be thrown out of office.
FPTP forces you to get at least 35% of the vote to win .