This is very true. But, the settlements should be abandoned. It's just too difficult to maintain them.
On what do you base this? Have you ever been to a "settlement"? Most are suburbs of Jerusalem, or Israeli towns built at high points along the green line.
I have family in Alfei Menashe. It is nine miles from the sea at a place where Israel is just seven miles wide. It sits on a high hill in the west of Samaria. On a clear day you can see from Haifa in the North, to Hadera, to Netanya, to Tel Aviv, and all the way to Ashdod in the south. Alfei Menashe overlooks about 70% of Israel's population. Do you know what it was before 1967? A barren hill with a Jordanian gun emplacement on the top. It was a place for Arabs to reign down death upon Israel.
Tell me, should Israel give up Alfei Menashe?
FWIW, Alfei Menashe is on the Israeli side of the fence. It is about five minutes from Kfar Saba.
75% of "settlers" live in such places, close in suburbs of Jerusalem or key strategic points along the green line.
30: That's a good route for the fence (... take in settlements that were built for security reasons along the green line, major blocs of Jewish population, and all of Jerusalem...)
Are you aware that your statement's 29 and 30 are mutually exclusive?