So the first pillar of my party would consist of a Tempest Cleric. You've got healing and AoE wrapped up in a nice bow. The second pillar would include this:
Var. Human Fighter 1/Warlock 4
Str 16, Dex 8, Con 14, Int 8, Wis 10, Cha 16
HP 40, Str Sv +6, Con Sv +5, AC 21 (Full Plate, Shield...