The best option would be a variation of a hybrid solution mixing numbers 3 and 5 from your list. In this case the international community puts real burdensome and painful economic, political and military pressure on both sides in an effort to force both parties into a mediated bilateral negotiation or a multilateral one. Options like genocide and ethnic cleansing would be forbidden under pain of military attack by international forces far stronger than either party could resist.
Certainly the international community should oppose any kind of genocide or ethnic cleansing. But the thing is that there's
been bilateral and multilateral negotiations already. Trying to build an international consensus to force yet another round of negotiations would presumably carry an implicit requirement of 'fairness' which leads straight back to perpetual deadlock. Trying for a 'fair' deal didn't work out, required more concessions from each side than presumably either was really happy with and was ultimately rejected by the Palestinians followed by a round of violent uprisings in the second intifada. The way things seem to be going since and to some extent before then, there's essentially a single problem; Israel (as the side both stronger and more comfortable with no deal) gradually pressuring the Palestinians, who perhaps will eventually negotiate and accept an 'unfair' deal as preferable to no deal at all. I don't know how much either side really cares about international opinion, but inasmuch as they do, endless disproportionate condemnation of Israel's actions, keeping embassies in Tel Aviv and so on only seems likely to slow or prevent Palestinian acquiescence, bolstering false hopes that East Jerusalem or other major points of contention are somehow still on the table for them; that if they just keep the conflict going longer they can eventually get more out of it.
What you seem to be suggesting turns a single problem into many; from a PR problem requiring Palestinians to accept an 'unfair' deal as better than no deal, to a PR problem requiring
both Palestinians and Israelis to accept a deal which will still require more concessions than they'd like (and in some regards will be
worse than no deal for the Israeli side); from more or less unilateral Israeli pressure, to trying to build an international consensus pressuring both sides.
Aside from the practicalities, there's the moral questions too. There's no real
good solution or course of action here, but some seem to be worse than others: Actively putting "real burdensome and painful economic, political and military pressure on both sides" would presumably create more hardship and suffering than is already present in the region, for however long those prospective rounds of negotiation take. Also the more heavy-handed external interventionism becomes the more dubious it seems, paternalistically telling the Palestinians that it's not simply good enough for them to accept the status quo as they are tacitly doing, or the Israelis that their concerns of security and access to holy sites aren't legitimate. If the Palestinians were making real compromising, conciliatory offers which the Israelis were rejecting then the purpose and ultimate endgame of settlement-building and so on would look a lot uglier; but as it stands they can be viewed largely as a way of applying pressure, and the Palestinians' choice not to back down on a position already proven to be untenable implies that their leadership at least still
prefer having no deal for now over the realistic alternatives. What right do uninvolved countries have to tell them that they're wrong, that they
must make a deal?