My recommendations lean on the Japanese-heavy side:
Sakura Taisen - classic adventure game with strategy isometric battles. see what the hype is about, and be blown away. it's like playing an anime.
Grandia - the definitive version of my favorite RPG of all time. the game was made centered around the Saturn architecture, and the voice actors are all top notch (Inoue Kikuko, Hidaka Noriko, Touma Yumi, Hisakawa Aya, Yamaguchi Kappei among others)
Grandia Digital Museum - although it is a fandisc, it's also a complete game in of itself. it's got 4 large dungeons to clear, with stuff to find. once you find everything, the game gives you an ending. best of all, they put effort into this fandisc by giving all the characters new spell chants, and for at least one character, spells you likely never saw in the original Grandia
Chaos Seed - incredible gem of a game that is a mix of aRPG, resource management, and building. it's a remake of a SFC game, and was voted among the top 10 of Favorite Saturn games by Japanese gamers. (FYI others on the list included Langrisser IV + V, Shining Force III Sce. 3, Yu-No (ranked #1), Thunderforce V, etc)
Tactics Ogre: Let Us Cling Together - don't really need a whole lot of Japanese to play IMO, but it's the better of the 32 bit remakes as it has voice acting and rearranged music, and minimal load. It's an excellent (hard) strategy game that requires planning and trying different things.
Langrisser IV + V - another recommendations for these great SRPGs. it's kind of like fire emblem except it has generals. units close to the general get bonuses. so it has a unique element.
Some non-Japanese intensive games include:
Burning Rangers - you asked about this, and someone answered and I would have to disagree with their reply. Is Japanese required? It is true that Kris gives you instructions vocally on where you should go to finish the stages. But 1) in any other normal game, you just explore and figure it out anyway. There's no reason why you can't do that here either. I've done it as I wasn't as fluent in Japanese as I am now when I played BR. and 2) For the meat of the game, once you beat the game once, then the game is all about finding the most hostages in the fastest time before clearing a stage for Stage Rank. But after you beat it once, all the hostage locations are randomized. Kris' vocal instructions do not help you at all with the hostage locations, and only tell you how to navigate through a stage. Since you already beat it, you already know how to beat the stage. So it's a matter of exploring every nook and cranny -anyway- for hostage locations.
Thunderforce Goldpack 2 - contains Thunderforce AC and Thunderforce IV. TF4 in particular is better here than the Genesis version because it removes the slowdown.
Radiant Silvergun - love it or hate it, it's a showcase of what the Saturn can do. beautiful looking game. and the game is sort of like a puzzle game in a shooter costume. not everyone's cup of tea, but it's extremely well made. I personally have more fun with it than Ikaruga.
Vampire Savior - great fighting games. 4MB RAM cart makes Savior far better than the wannabe PSX one.
Fire Pro Wrestling 6 Men Scramble - at the time it was the most revered wrestling game because of the technique it involved. but since they have FPWD for Dreamcast, and also the GBA iterations, I'm not sure if this one is the king anymore. Still a great game, and 6players on the Saturn.
Sakura Taisen Hanagumi Taisen Columns - basically columns with a ST theme, which changes the gameplay since there are "supers"/hissatsu that you do once you fill up the meters. Kind of like SPFIIT in that way.
The other Capcom 4MB ram cart fighters depend on how much you like those respective games (XMvsSF, Marvel vs SF, SFZ3). But SF Zero 3 in particular has the correct aspect ratio compared to the arcade. The Dreamcast Zero 3 is like an upgraded version of the PSX port.
