There is now nothing that fun about having a fast time in parkour, so my suggestion is going to change that.
Medals:
medals are items you can get for finishing a level in a % time
Gold = Finish this level in (The fastest time possible + 2 seconds)
Silver = Finish this level in (The fastest time possible + 3 seconds)
Bronze = Finish the game in (The fastest time possible + 5 seconds)
Person with no medals:
Person with a few medals:
Medal rewards:
Every medal gives you loot points,
Table:
Easy:
Gold = 30 loot points
Silver = 20 loot points
Bronze = 10 loot points
Medium:
Gold = 40 loot points
Silver = 30 loot points
Bronze = 20 loot points
Hard:
Gold = 50 loot points
Silver = 40 loot points
Bronze = 30 loot points
With this suggestion it is possible to add a few challenges:
Get bronze on all the levels: 3 cubelet
Get silver on all the levels: 2 super cubelet
Get gold on all the levels: 1 uber cubelet
Also:
Win 1 competitive game = 100 loot points
Win 10 competitive game = 200 loot points
Win 100 competitive game = 1 cubelet
Win 500 competitive game = 1 super cubelet
Win 1000 competitive game = 1 uber cubelet
Now something secret:
If you get all gold medals on all the levels you can unlock a New medal: The diamond
Diamond = Finish this level in (The fastest time possible + 1 seconds)
When you get all the diamonds on all the levels you get 5 uber cubelet and a special gadget. (idk what gadget, or a trail...Maybe you suggest something?)
Medals:
medals are items you can get for finishing a level in a % time
Gold = Finish this level in (The fastest time possible + 2 seconds)
Silver = Finish this level in (The fastest time possible + 3 seconds)
Bronze = Finish the game in (The fastest time possible + 5 seconds)
Person with no medals:

Person with a few medals:

Medal rewards:
Every medal gives you loot points,
Table:
Easy:
Gold = 30 loot points
Silver = 20 loot points
Bronze = 10 loot points
Medium:
Gold = 40 loot points
Silver = 30 loot points
Bronze = 20 loot points
Hard:
Gold = 50 loot points
Silver = 40 loot points
Bronze = 30 loot points
With this suggestion it is possible to add a few challenges:
Get bronze on all the levels: 3 cubelet
Get silver on all the levels: 2 super cubelet
Get gold on all the levels: 1 uber cubelet
Also:
Win 1 competitive game = 100 loot points
Win 10 competitive game = 200 loot points
Win 100 competitive game = 1 cubelet
Win 500 competitive game = 1 super cubelet
Win 1000 competitive game = 1 uber cubelet
Now something secret:
If you get all gold medals on all the levels you can unlock a New medal: The diamond
Diamond = Finish this level in (The fastest time possible + 1 seconds)

When you get all the diamonds on all the levels you get 5 uber cubelet and a special gadget. (idk what gadget, or a trail...Maybe you suggest something?)