I really think that the Harvest Moon series is the most original out there. When the first one came out for SNES, the idea of being a farmer, doing RPG like tasks, and having a set time and calender was the only time we've seen that in a game (that I know of). Even today, I havn't seen an other HarvestMoon-type game out there, just more great Harvest Moon games for GC and GBA.