D&D spells are based on myths, legends, fairy stories, parables, and modern pop culture. To stay faithful to this tradition, spells shouldn't just be a collection of dice and effects. They tried that in 4e to a greater extent and leeched a lot of character out of the characters. I think 5e is very close to the sweet spot to please most of the people most of the time. The variation in clerics works really well in play without them eating up the wizard like 3e CoDzilla. If you want to tweak your Cleric further, I think modification of channel divinity works better than opening them up to a much wider spell selection.
While the 4e thing was more a false perception based on the least interesting or distinct powers, I agree entirely with the point of this post. I’d love for each class to have a few more spells unique to them, not fewer.
Bard: Songs. A suite of spells for each tier that emulate the 3/.5e bardic Song of X features. Maybe concentration, but preferably not, your allies get XYZ benefit or your enemies get ZYX debuff while within whatever range. Also some unique end tier spells that do some epic mythic stuff related to the power of stories, songs, insults, and doom-speaking. Up to and including raising the dead by recitation of a Requiem for that individual, calling the heroic dead of legend into the world to ravage the enemy or accomplish some other task, singing innanimate things or beasts into helping the party/building something/whatever, and causing several creatures to fall down and weep uncontrollably, cower in shame or fear, or reconsider their animus toward the party.
Druid: spells that make nature come alive (more summon spells, with plant creatures, earth golems, treants, etc), a cantrip that makes a weapon attack and adds poison or acid damage, and at level 5 poisons the target. More spells to take on animal traits and traits associated with nature’s guardians and stuff, like treants, dryads, wood woads, etc. spells to buff all beasts and fey within range. Some of these would be shared with ranger, some not.
Cleric: Cantrip that does a weapon attack and makes the damage radiant, then adds radiant damage as it scales. Another that does 1d4 radiant to 1 enemy within 5 ft, then adds 2 enemies per scaling tier, as well as adding damage to the primary attack. Spells to create beacons upon enemies you hit, so that something extra happens when an ally hits them, like radiant light flaring with each strike against the Beacon target, or the target glows with sunlight and passively hurts its allies nearby, etc. the cleric should be able to single out enemies as the target of he gods’ wrath, and give benefits to allies for meting our Divine Justice.
Warlock: spells to make stone and wood and whatever else is nearby come alive to grab at enemies, make enemies sink into the ground/floor, turn surfaces into pools of acid, and also more fun utility spells that no one else gets. Also things like summoning swarms of critters, making someone’s shadow come alive and attack them, etc. a solid enough melee cantrip that Hexblade isn’t necessary for a melee build, or the hex-blade lock can skip the extra attack invocation. Life drain type spells, rebuffing aura spells, some of which would target an enemy and make them dangerous to their own allies. At high level, spells that turn summoned or controlled creatures against their masters.
Sorcerer: More spells like Chromatic Orb. Unique summoning spells that manifest a very simple creature of elemental energy and limited intelligence, totally dedicated to the sorcerer. Like a powerful thought form type deal.
Wizard: none. They’re fine.
Ranger: pet buff spells, and a resurrect/summon Beast spell, written so that it can bring back a slain beast companion, or summon one that isn’t as good as the BM pet, and if it’s a pet you’re bonded with it has an extra benefit. Spells that combine within a weapon attack that aren’t concentration, and that do more interesting stuff, like create a swarm of insects filling ten feet around the target, or a cloud of poison fumes, or needles explode outward. Get enough control options that a ranger could reasonably focus on that.
Paladin: more smite spells? Some lead the charge type spells. Spells for Reactions that punish enemy tactics that hurt the Paladin’s allies. Spells that mess with casters. Spells that deal extra damage to summoned or controlled creatures, and send some damage on to the creature controlling them, maybe also lighting the summoner up for allies attacks in some way?
