What is the difference between a druid and shaman. Perhaps we should just rename the druid to shaman to alleviate the "only orcs and trolls have shamen" problem.
My ''hot take'' would be to merge bards and druid as one class of loremaster, people leader and spellcasters in deep connection with the traditions of the world and folk magic fueled by communal connection of people, their past and their aspirations. Druids, shaman, skald, galdr, seidr etc would be from that class, to play character such as Merlin or other edge mages. Lets call them Mystics. They use speech, companions or music as spell focus.
Then you would merge cleric and warlock for casters granted powers through their devotion or service to a Power or Belief. No need to have patron and domains. Lets say you have class archetype like ''The Fiery One'': could be use for a priest of a God of fire, a demon from the burning hells, a volcano primordial, a effreeti lord or even a philosophy based around the idea that fire must be brought to the coldest, remotest places in the world to unite people together. Call them Avowed , Cultist or Acolyte. They use sacrifice and offering as spell focus.
Then merge Wizard and Sorcerer for those who use or are infused by the magic of the matter. Lets call them Mages. They are focused on the perceptible results of spellcasting; a the factual design of a spell is to create an effect. While the Mystics and the Avowed are more in negotiation with magic or its source, the Mages calculate, studies and thinker with magic around them or within them with the explicit expectation of a desired result. They use tangible esoteric tools as spell focus.
Then merge Paladin and Rangers. Call them Warden because they are sworn to protect a cause: good vs evil, freedom vs tyranny, civilization vs wilderness or opposition to a specific foes. No matter which side they are on, the Warden is protecting a personal ideal and such focus gives them access to a small number of spells. The Warden is its own spell focus.
Then merge Rogue and Fighter. While other sacrificed their time to master an outside force, the Adventurer perfected one thing: themselves. Knaves, mercenaries, veteran soldiers and dungeon delver, they all focused on their own skills, earning a mastery of social, physical or weapon skill. While other succeed by the power of magic, the Adventurer is relying on its own wits, strengths and presence to resolve the situation they encounter.
Then, final hot take, merge the monk and barbarian to create a class focused on attaining a second-state to shrug off pain and normal worldly restraints. Be it with a trance, rage, cold fury or ecstasy, the Champion is able to forgo the use of mortal instruments such as weapons and armors and keep their mind focused on their goal.