Horchata in the U.S. and northern Mexico is almost always made from rice, but other nuts or seeds can used. Almonds are very good.
On the sammich front, the Cuban pork sandwich and the Vietamese bánh mì compete well with tortas for my money. Mexican bakers have steadily diminished the quality of their breads over the years, adopting the tasteless, almost textureless, mush style of American mass market swill. As a result, I find it easier to get good bánh mì or Cuban sandwiches than tortas.