For validity the bread must be wheat bread, the wine in both east and west must be grape, and have no additives or special starters, just grapes and the natural yeasts that cause the fermenting of the wine. In the East yeast bread is required. In the west we use unleavened bread. In the west it is illicit to use leven in the bread used for the Eucarist, and in most of the east it is illicit to use unleavened bread. Many in the east believe that the last supper was the night before the passover seder, in the west we have always interpreted the last supper to have taken place on the first night of Passover. (Remember the Jewish day begins from sundown to sundown, not at midnight.) All Jewish festivals begin at sundown.
Some Eastern Catholic and Orthodox do reserve the Blessed Sacrament. In some of the Churches they which have a large enough altar they have tabernacles (many look like a small golden model of a church,) others have a small box on the altar surrounded by a throne which they refer to as a casket, a few have a hanging aumbry in the shape of a dove. Some do not have any and the priest reserves some of the consecrated bread in the rectory in a special shrine. As there was never a denyal of the real presence in the East like among the Protestants in the west, the cult of the Blessed Sacrament, or the external manifestations of devotion like exposition, benediction, Corpus Christi etc did not develop to manifest the devotion and to support the traditional belief.
See this webpage for more on the Eastern Catholic Sanctuary