Kremling's Revenge is a pretty neat hack, yeah.
It does have a few flaws, though, and it doesn't entirely escape from the whole "kaizo" descriptor. Later in the game, you'll find lots of sections of levels that are just narrow platforms with Krushas on them. Also, all of the water levels aren't redone at all, unless you count cutting them from the game entirely, as they've all been changed to a single screen-length each.
Platform Perils (the last level) is, appropriately, by far the most difficult, and I actually did a makeshift TAS of it myself a little less than a year ago:
Link to video
Not very optimized by any means, but it was more of a demonstration than anything.
I wouldn't be completely opposed to seeing a full-game TAS, though. Some of the levels have some interesting features and it would be entertaining to see a "perfect" playthrough.
I've been a lurker here forever, but I simply can't resist commenting on this one.
Between:
Link's complete shock at suddenly being on top of some tower somewhere and seeing a dude die right in front of him, followed by possibly getting a little action on his way out,
Link's "lightsaber" at the end of the Ganon battle, and
The hilarious distance between Ganon and Link during the freeze-frame after the final attack making it look like some terribly-staged play,
I'd say this is a contender for one of the most entertaining TASes of all time. Thanks for this, SwordlessLink! As usual, you've made my day.