At least for now, these changes are probably too much to hope for. Coalition governments have held power in Japan ever since 1993, when a group of parties ousted the LDP from power and made Hosokawa Morihiro prime minister. Compared with some of the major European countries, Japan has had little experience with coalition rule, and there was a great deal of confusion at first. Then there was the strange wedding of traditional enemies, when Socialist leader Murayama Tomiichi allied his party with the LDP and became prime minister. Still, looking back over the last seven years, it seems clear to me that Japanese parties have gained some knowledge of how coalition governments work.
Parties are but tools for grasping power and implementing policies.
To come into power, you sometimes must shake hands with the devil. More than that, since agreements on which parties to include in coalition governments must await the election results, parties may have to forget the criticisms they hurled at each other during the campaign. This is how coalition politics works. What is important is that the newly formed coalition reach a firm agreement on its policy platform and steadily implement the measures in it.