Retro-propulsive landing
Pros:
- Fine control over landing location
- Softest landing of all
- Cheap re-usability
- Potential to land on bodies with little or no atmosphere (mars, the moon)
Cons:
- Anything near the landing location will get burnt to a crisp
- Expensive production
Parachutes
Pros:
- Cheaper production
- Safe landing (unless you happen to end under the drop-pod)
- Passive system requiring little supervision
Cons:
- Unable to land on bodies with little or no atmosphere
- Little control over landing location*
- Little potential for re-usability
Hard-landing / Lithobraking
Pros:
- Fast delivery
- Cheapest production
- Can land anywhere
- Requires no supervision
Cons:
- Very hard landing, unsuitable for human use and delicate cargo
- No control over landing location*
- Non-reusable
Bottom line
Considering the above, I'd say each system has it's uses.
Retro-propulsion is best for landing delicate cargo and people in friendly territory on designated landing locations or behind enemy lines for critical missions (too costly to use unreservedly).
Parachutes are a good way to drop cargo or people in a wide area, useful for for large scale attacks or incursions where precision is not essential but numbers are.
Lithobreaking is a practical and inexpensive way to quickly deliver durable supplies such as food, water and certain types of ammunition in case of an emergency.
* Both parachutes and hard landings can be guided with specialized equipment (steerable parachutes and aerodynamic control surfaces) in exchange for an increase in cost and the need for active control and guidance systems
If you are asking about the benefits of an orbital drop versus a non-orbital drop, then it simply depends on whether the things you are dropping come from/are manufactured in space.
If you need to lift things to space just to drop them back down in the same planet then it hardly has any benefits at all. Unless you have an inexpensive way to get things to space, such as a launch loop, in which case the greatest benefit is speed.
