Anyways the reasons why tracks like Hit Em' Up, Ether and The Ripper Strikes Back are considered ultimate diss tracks is cause they're just right in your face.
Cmon, does anyone actually want to listen to a monotone Lloyd Banks throw out diss tracks? You can spit some of the meanest and wittiest lines ever, if the emotion or intensity is not backing up people won't bother.
Hit Em Up - I think the way Pac spit it was just viscious. Simple rhymes and disses that cut.
The Ripper Strikes Back - Good rhymes, and probably one of the best lines I've heard "99 Percent of your fans don't exist" but hearing LL just going nuts on the mic made people open their ears and cop his album. There's a reason why he thanked Canibus in his album booklet that year.
Ether - Once again, simple rhymes, maybe not as intense as Pac but the way the track was put together made it look pretty damn hard. "Fuck Jay-Z" is one hell of a way to start something and it worked for Pac. Also, Nas did have some good lines in there like it or not.