I have been getting a kick out of Final Fantasy 1 and A link to the past randomizers.
Figured I'd post links to where to get them for those of you who might be interested.
Most of these games randomize chest contents. some of them swap entrances and exits to levels, powerups, cities, enemy spells and locations.
These were all designed to be able to still be beaten, and I have never generated a randomizer seed that was impossible(except with super mario world if you allow the randomizer to remove water from levels)
Love that it adds near infinite replayability to these games.
I play on an everdrive cart and I do own original copies of these games as well.
super mario world randomizer
http://authorblues.github.io/smwrandomizer/
a link to the past randomizer
https://dessyreqt.github.io/alttprandomizer/
final fantasy 1 randomizer
https://github.com/Entroper/Randomizers/releases
zelda 2 randomizer
https://bitbucket.org/digshake/z2randomizer/wiki/Home
zelda 1 randomizer
https://sites.google.com/site/zeldarandomizer/
There are many more, but these are the ones I have used and can confirm work well.