I’m particularly a big fan of many of the songs from Nobuo Uematsu (FF8 and FF10 soundtracks in particular) and Yasunori Mitsuda (Chronocross soundtrack in particular.)
Any suggestions of some game soundtracks which have styles similar to those soundtracks that I could look into?
Some obvious choices would be xenogears and xenosaga episode 1 and Shadow Hearts and SH: covenent since Yasunori Mitsuda produced the music for these games as well as the ones you mentioned.
As for similar styles of music I would go with the psx recording of Ogre Battle, Dawn of Mana, and Radient Silvergun. another one you might want to try as well is Odin Sphere.
Well I hope this helps you.
Note: Just a helpful suggestion: You porbably wanted to post this within the anime and general video game music section instead of here since you are looking for music outside the final fantasy series. Also, this area is mostly for the discusion of the final fantasy game’s storylines, characters, and quarks. We usually talk about the music within the music specific catagory.
And thanks for the suggestions.