My favorite is Phantasy Star 2, it was the first RPG I got played and had gotten into.
I played it for months over and over again back in 1990 and have been hooked on the series since then.
I have so many memories going thru this game and using the hint book that came with it
I love playing the others and each game has a spacial thing about them, PS III has the different main characters that you get to play as in each generation with 4 endings.
I didn't like the battle setup in it though.
PS IV was the longest and had a great story, cool techs.
Phantasy Star had the 3-D dungeons .
Playing the online or universe games just left something out what is was like to go thru the original series, like characters, story game play.( I'm not saying they was bad or anything)
I can't wait to Play thru Gen 1 and 2 when they are finished.