I thought SoM was the start of A Japanese-made brand of Diablo-like gaming back in the day. I would have figured I'd play many games like it going forward, and that the option of co-op RPGs would have thrived...
... yet, with Seiken Densetsu 3 never making it over to the US, options seemed to become severely limited. I don't think anything gave me the feel of Mana until maybe... PSO? Legends of Mana's stiff 2P really soured me on it, but it was a very great experience on it's own, and I really grew to like it!
I'll be replaying SoM again once it appears on US WiiU VC, but man... such a game, such a series. It's so weird how long such great ideas and gameplay can sit and be forgotten, while others get iterated and cloned multiple times a month, let alone a year.