My first RPG was the first Dragon Warrior. I enjoyed it a lot but never really got into any other RPGs until Super Mario RPG. It was definitely the inclusion of Mario that peaked my interest and I loved it throughout.
This was the first Mario game to give the characters any kind of personalities. The most prominent for me would be Bowser. I remember it was such a big deal to have Bowser playable, akin to recently with Sonic being playable in Smash Bros. And Bowser being a hapless bad guy is still prominent today.
The actions and emotions of the characters were really entertaining back in the day. And Mario falling on his face and miming is still funny today. On another note, my friend and I always thought it was weird how your party members literally hang out inside of Mario. We always said they went into his pocket.
As far as the technical aspects go, I don't have any problems with the graphics. I'm playing the game on my SNES hooked up to my plasma. Still images of the characters are kinda ugly, but the personality Square gave them overcome that aspect.
Like I said before, I really enjoy the battle system. I love the timing setup and is exactly as I remember. I like how different weapons actually change the characters attacks in battle. I'm not a hardcore RPG person, so maybe this is common. But in the few RPGs I have played, better weapons tend to just up the attack stat.
I remember the game not being all that difficult other than a few bosses, but I had zero issues this playthrough. Maybe it's how I leveled my characters? My final group was Mario, Princess (for healing) and Geno (for attack/defense boost).