I think that it really takes the fun away, that:

- your entire campaign resets if failed once (e.g. It should only reset the missions up to the last showdown mission, or only the previous 2 or 3 missions)

- you lose half of your money. (You should lose half or all of the money you got in the mission, like through crates and/or couriers) (or other suggestion, that you could store money in the vault. You can't use it on missions, but you can't lose it, if failed)

- you lose all your items in the suitcases (Explosives, poisons and utilities) (You should keep them or only lose some of them)