It would seem from the Rambam (Hilchos Teshuva 9:2) that the ikkar reason to want mashiach is to get rid of the oppression of the nations so that we can learn more Torah and do more mitzvos, thereby earning more Olam Habah:
????? ?? ????? ?? ????? ??????? ??????? ????? ????? ??? ?????? ??????? ????? ?????? ??? ????? ????? ?????? ????? ?????? ??? ????? ????? ????? ??? ????? ???? ????? ???