jgsugden
Legend
Is pretty decent 6d12 using sorcery points (so effectively a spell) at 11th level (to 2 targets)? That is fine, but not impressive. Sharpshooter builds, Sorlocks, etc... are doing a lot more....Cantrips with saves are fine in "melee" combat. Death Cleric and death cleric 1/Divine Soul XYZ I've seen put out some impressive numbers....
I found Fireball and Spirit Guardians to be very different experiences....I tend to think in most situations that fireball > spirit guardians. So that I would agree with. Also burning hands on a high AC caster that don't mind to mix it up in melee. Amazing. Oh, and let's not forget about the light cleric channel divinity AOE. So yes, I'm a big fan of the light cleric too. It's probably the best AOE focused character in the game...
Against 'minions', both are useful, but I found that Spirit Guardians generally killed more. The damage from it was often enough to clean up goblins, stirges, etc... Then I could reposition to take out more. The Fireball tended to be overkill, and unless you were an Evoker, it was often hard to hit all of the enemies you wanted to hit with it without hitting the party. Spirit Guardians is much more selective. In these situations, even when the spell dealt less damage overall, it tended to deal more effective damage (which is total damage less overkill damage).
Against bigger solo enemies, the fireball was often a better use case between the two, but was not the spell I'd use. A single target spell or enhancement like haste was often more effective for the group on round one. Still, I did upcast Spirit guardians to great effect on occasion in solo combats. A 5th level spirit guardians that hangs around for 3 rounds is a lot of damage against a powerful foe. If you get it up to 4 rounds.... And if that solo isn't solo but has some fodder for protection, it keeps them distanced from the BBEG.
Also, the difference between fire and radiant damage is huge. It has meaningful impacts on undead, and there are a lot of non-undead that have resistance to fire, but not radiance. Radiance resistance is fairly rare.