New Star Ocean IV trailer shows off ridiculously lovely characters

I know I won’t win any fans with this guilty admission, but I have never played a Star Ocean game. Of course, seeing screens of the upcoming Star Ocean IV have made me think I might be playing my first one very soon, and the new trailer posted on Square-Enix’s YouTube channel pretty much clinches it — I need this game. Go watch it!

So, Star Ocean fans, I humbly ask for your guidance. If I play Star Ocean IV and fall in love, can you suggest what other games in the series I must get my hands on>

[Thanks, Christian!]