I´m a huge Rune Factory fan and have played all of the games.
Every game has something unique, you can just edperience in this game.
RF1: New concept of Harvest Moon plus dungeons.
RF Frontier: "Runies", who will influence the ground-type and vertility.
RF2: Continue the story as your child and marry the children of the other couples.
RF3: You play as a half whoolie and some of the bachelorettes are halfmosnters, too.
RF Tides of Destiny: You have to explore a bigger environment (an huge ocean) to find islands with dungeons on it. Also you can play as a girl (but there are more bachelors, than bachelorettes).
RF4: Play as a prince/princess and use the special earned points to rule the land. There are more special bachelors/bachelorettes (not like in RF3) and the same amount of bachelors and bachelorettes (not like the 8 bachelorettes and 3 bachelors from Oceans).
I really liked RF3, because of this halfmonster bachelorettes.
Not every bachelorette is obvious a halfmonster so it´s really intresting, how the bachelorettes and townspeople cope with your secret and the halfmosnters.
If you´r intrested, just watch some walkthroughts from youtube.
