What happens if Shinui ends up holding the balance of power? What's the chance they'd join a left-wing coalition with Labor? If they join with Likud, what limits does that place on Palestinian policy? Can you make a right wing coalition based on Shinui and Likud that doesn't include the religious parties? Can Shinui co-exist in coalition with any of the religious parties?
If the religious keep their draft exemptions, etc., but are cut off from special funding by the state, will that blunt the resentment of most secular Israelis? That is, do they mind forking over tax dollars more, or do they mind the (informal) special status accorded the religious?
Shinui could join a "centrist" coalition together with Labor and Likud, if Labor were willing to go that direction. The arithmetic wouldn't countenance them joining a left-wing gov't, and I think their leadership wouldn't be interested either. In their campaign, Shinui is trying to "triangulate" on the security/Palestinian issue saying: we're not overaggressive like Likud or pushovers like Labor. Shinui can NOT coexist with religious parties, which will make coalition-building hard for Sharon.
It's difficult to imagine signifcant change regarding Orthodox draft exemptions and funding. Maybe funding would be reduced somewhat, but the Arab parties also support the Large Families law, and the IDF is not in any hurry to draft thousands of Hasidim etc.
More: RibbityFrog mentions that some people think that a Likud-Labor-Shinui coalition would undermine core support of the Likud. Gil says that the leader of Shinui has said he would be willing to be in a coalition with the National Religious Party, as their supporters serve in the Army and are not reliant on gov't assistance; but the NRP might be more hesitant.