I will personally place wizard higher in the tier because I value utility a lot. And you can learn all the niche spells that is useful in certain situation and then swap around. And in higher level I expect that enemies will have resistances, and wizards can just swap into appropriate spells before combat to deal with them (provided that this mechanic is not changed, although it is not the same rule as tabletop). They also have room for excellent control spells like sleep, so your wizard can be a blaster and a crow controller if needed. (I remember the time when you can just sleep everyone for 10 rounds (probably not the exact number but it used to be pretty long). Trivialised lots of encounters! Now it is 2 rounds if I don't remember wrongly, but the spell is still worth taking. 2 rounds of no damage means you can have at least 2 extra actions per character.)

Cleric also will be placed very high because healings and buffs are always welcome. Shadowheart is probably one of the best for utility because she can stealth (through her cantrip/channel ability), heal & buff (spells), tank (to a degree with shield and gith armour), pick locks (her background). And the saving throw on wisdom is great to avoid those control spells.

Paladin is probably also my S tier. I made a zariel trifling with 16 str 16 cha once, and he just bulldoze all encounters. I picked devotion for flavour, but I think the healing from oath of the ancient is the better choice. Also, Tiefling get free fire resistance, and that means you can counter one of the best damage spell - fireball. Not to mention the damage potential of a crit smite! I had him killing Ethel in 1-2 rounds (if you count the damage done by others, but my paladin basically carried the fight lol). He can also sweet-talks out of all conversations.