Im going to address them by class.
Barbarian has more strength and more blessings than the Fighter, but the Fighter can use its abilities far more often while the Barbarian has to Bury cards which generally limits the ability to only to cards you find.
Bard is good for support but not good solo. You have to pick the Virtuosos role to be better as solo character. He's technically the worst spellcaster. He is way below the others on spell roles and he doesnt have any strong starting offense. He can be quite good once you get certain power feats to pass any skills checks. Biggest problem is whether you want to heal, carry attack spells, or try ranged attacks.
Cleric is even more specialized than Paladin. Its more dedicated as a healer and once you get into Roles the Cleric becomes a living Blessing beacon as it can recharge/put on top of your deck eventually. Unfortunately it is weak with few weapons and spells so needs them itself as it only has a d6 strength and doesnt have any feats to boost recharge.
Druid is quite good. It has alot of spells slots and can improve its own checks by revealing and animal ally. In melee its much weaker than Monk. Hard choice of whether to use damage spells, cure, or split.
Fighter is decent but has few blessings and more weapon slots than he would really ever need. His ability to use weapons for their effects and only recharge them can be quite useful.
Monk is quite good once you figure it out. With the ability to recharge blessings it uses for its own combat it can breeze through combat checks. the Monk doesnt start with weapons so unlocking more is critical as it
Paladin is terrible to start off as few weapons and Armor as its favored card. It gets better but when it really shines is higher tiers where you can have alot of blessings you can recharge and scout through locations without losing boons.
Ranger is very good at scouting and support, but not so good solo. Its because there arent many ranged weapons that have an effect on yourself. Its not an easy choice between Roles as one gives you d12s to your dexterity checks, while the other allows you to recharge animal Allies
Rogue is good at scouting because it can freely evade banes and boons. Its starting attack power is weak, but with more weapons and blessings its easy to solo locations.
Sorcerer does what the Wizard tries but it feels better. She has less spells but has the Blessings to balance that out. She automatically recharge spells, and in case you dont have attack spells she has Arcane Blast. Her two roles are mediocre however.
Wizard's lack of Blessings is a major handicap. It means he cannot improve his, or others attacks. Both of his role choices are mediocre as they take several feats but dont give a powerful bonuses. He can be fairly strong and surprisingly durable if you specialize in attack spells as he can improve his recharge and carry alot of damage reducing items.
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Major problem is just acquiring multiple versions of cards so you can have your party fully equipped. Thieves Tools and the like are very useful. Some underestimated classes can function quite well with self-healing or anti-trap cards.
Some characters start out looking bad but end up quite good. Paladin and Cleric can be regular sources of Blessings for your whole Party after a point. Any feats related to improving Blessings in any way is quite useful.
The specialized roles characters can pick later vary wildly. Some barely matter, others have a clear winner between one and the other.
