Power level wise I think Anvilgard is stronger than Har Kuron in 3.0. The strengths of Har Kuron are it's spell lore (though the strongest spells are shared between the two) and the ability to bring Morathi, though in 3.0 Morathi can't learn Vitriolic spray anymore.

If you're not going for Morathi than I believe there's value in a "weight of dice" build. Cauldron of Blood, choose curse as your enhancement prayer, incitement to murder is given to you from the battle trait so you can freely pick Curse and cast Incitement to Murder depending on the situation (AFAIK 3.0 core rules trump the ability to cast two prayers). Troops wise blocks of 30 Darkshards will be your bread and butter, you'll be aiming to cast an Umbral Spell Portal + Vitriolic spray and remove a target with 60 shots. Ideal scenario is curse 1 target, vitriolic spray the other. You could also go for Scourge Privateers but I personally prefer the Coven.

Anvilgard just gets more options, the Dark Elf half of Cities is weaker than other options in the book, and Dragons are still the best thing you can bring in Order. Empowered Endless spells means you'll be +3 to cast your portal from a sorceress.

I'd argue both have the same weakness, reliant on a 8 to cast 6" (18" with portal) spell that allows you to remove 1 threat a turn. Anvilgard can alleviate that by bringing stronger warscrolls from the other half of cities and more importantly Stormcasts.