I've found, in the game's current state, that Hex: Wisdom works best to help with Shadowheart's atrocious default damage cantrip and Hex:Dexterity to help support Lae'zel's STR-based pushing tactics or casters using grease and ice.
Yea why is Shadowhearts cantrip so bad anyway? Firebolt is good, Eldritch Blast is amazing, but you get maybe 55-60% chance to hit on a good day with Sacred Flame, and that's with the high ground.
Sacred Flame seems gimped compared to other cantrips. Or maybe it's just that firebolt and Eldritch Blast are so much better than all the other cantrips.
Technically, both Firebolt and Eldritch Blast attack the target's AC and thus fall under the height rules for advantage, etc.
Sacred Flame does not target AC, thus you are directly affecting the mob's saving throw and not AC and can't gain advantage for height, etc. You can, however, blind target a mob with Sacred Flame and the same can't be said for the other cantrips that require line of sight.
I tend to Hex against whatever CC save I need, the spell tooltips should tell you what save they target, but against goblins I just hex to add to the damage because they don't have a ton of hp anyway.
Hope that helps!
Sheyde