I used to say it was a toss up between A Link to the Past, Secret of Mana, and Super Metroid, because they’re all 10/10 games. I just haven’t been able to do the latter two lately. They’re not hard, I just don’t stick with them.
If you also play A Link to the Past, you should know there is a Randomiser that combines them. You start in Super Metroid. Going into a map room takes you to a random fortune teller and vice versa. The way both games are coded, none of their items share an ID, so you can find Metroid items in Zelda and Zelda items in Metroid. And it just works. Of course Link can’t use power bombs and Samus can’t use the Hookshot. The items are game specific. The goal is to beat Ganon and then Mother Brain and escape. I really can’t do that one.