Try Ignite Mage with Fireballs or Meteor. There’s a build on the forum. You will need some Unique items for best results, but they should drop fairly often.
Black Hole just got nerfed though, but it should still be fun to play with.
There’s an Aura of Decay build on the forum as well (“Toxic Meltdown”), but you’ll need to prioritize health regen/poison protection gear, some experience with crafting system will be necessary.
if ou don’t mind a build where minions do the DoTs for you, a Necromancer summoner with poison Wraiths or bleed skeletons might suit your taste. Doublet of Onos Thul is recommended for bleed summons.
There are some poison-themed Primalist builds, but I don’t know how well tuned they are, to me they look like some hodge-podge of poison themed skills.
There are also Primalist caster build with Entangling Vines/Tornado, which are
technically Physical AoE DoT spells.
Sentinel may have some DoT potential, but Time Rot specifically does very little damage per se. You’d better look for Paladin Ignite builds (Holy Aura with maxed Flame Burst, Paladin’s Holy Bolt etc) or Void Knight builds with Devouring Orb / Hammer Throw DoTs.