This is a lot to place on the DM, but I like the anarchy of a system like dungeon crawler classic. You expect some of your characters to die, e.g. in one adventure my character in a last ditch effort to save himself drank a potion of unknown origin, that potion turned him into a mithral statue. It was a fitting end to his short but eventful life.
Another character played by a different player managed through a long process involving books and negociations with his patron to construct a demonic sentient flying dog through whom he could cast spells and see.
This kind of exploration I think encourages players to see their characters much more as characters than machines to be min maxed and it is way more fun.
Give the DM total control to decide the dice roles that determine the outcome of the shenanigans. You try to hire an army of peasants you're going to be dealing with appointing sergeants, logistics, mutany, desertion all before you try to line them up to throw a ladder at some dude, which in the end is probably like a 1d20 >= ac for a chance of 1d4 damage, with of course crit tables, where on a critical success the dude might be tangled up in the ladder and fall over or something.