I might have done more Abyss runs since 1.4 than anyone else on this sub, going from 70 to 85 with it. After 1.5 I also revisited Recommended+ for finding out the most time efficient way to farm golden chests (for Grand Souks, Arentine and Opals), as Exp and gold were no longer valuable for me anymore.

That said, Abyss has changed quite a bit for both levels regarding difficulty of certain mobs and optimal gear.

I won‘t write another guide on this (much stuff on this topic can be found under my username) but battling 6x dragons (not only undead ones), 6x liches, 6x Wispmothers or even top level Atros of any kind or Dremora without specific elemental resist is the wrong way to do, because any approach to farm Abyss includes reliability. If you fail in one or two out of four or five your farming average goes down the drain.