I liked the original, but haven't seen it in a while. Still, the changes are significant and hard to overlook.
It looks like a theatrical film now, thanks to the framing, color grading and better, not on-the-nose, lighting. Altered animation really works and streghtens the script; blood is the one thing missing in famous Joker scene and using plastique instead of batarang in final confrontation ties good to the first Batman fight. But the best thing is getting rid of exposition and building up the reveal - it really works, even when I knew what was gonna happen.
Really liked the cuts and changes, although I don't like shortening already short movie and miss the Batman racing scene, but can't always get all what you want.
The editing is flawless to me 10/10, the movie itself 8,5/10. Great job, Uncanny Antman!
Would like to see more DC animated movies improved (maybe Green Lantern First Flight, which is already solid)