You should rebalance the warrior, starting by swapping the archon and hero zealot, because with that, all mercia and swamp quests are too easy even solo. Just use berserker, then shields of valor, then wait for them to cool down and use a mana potion, rinse and repeat. Devilkin is killed after like 3 hits with about +10 dmg upgrade.

Near the start of the game, the rogue is unreachable. the path to him is too small for any characters to go through.