Well, ritual spells have no use in combat, usually, they are divination or support spells.
PD: The only exception would be the creative uses of spells like find familiar, phantom steed or unseen servant, for example.
I'd add Tiny Hut and Forbiddence to that list. If you know an enemy is coming for you, cast tiny hut and you will have it's defences when when they attack. Forbiddence can do a lot of damage to enemies, but you have to know they are coming in advance.
Not a ritual, but a fun thing to do with Wish is casting spells that normally have a time consuming casting time as an instant action. So Forbiddence, Geas, Planar Binding, Temple of the Gods, and Mighty Fortress become combat spells all of a Sudden when cast via wish. The only spells that can come even close to how good Wish is are Gate, True Polymorph (use this to creation an army of monsters or grant immortality to your friends), and True Resurrection (the Githyanki dwell on the corpse of a dead God, cast True Resurrection on it and watch the Githyanki city be destroyed).
Actually maybe Augury, Commune with Nature, and Commune as well if you get key tactical info that you can apply later in combat.
