More variety in challenges

[Alayan-stk-2]

I already talked about it here

• Introduce a significant number of challenges using reverse direction
• Have 2 or 3 nitro challenges still
• Have 2 skidding challenges
• Have several races against ghosts
• Have some standard time-trial races too
• Have a egg hunt or two, with adapted theming and some surrounding story development
• Have a battle or two, if the mode can be improved enough to be more interesting and to not have the duration of the battle strongly dependent on powerup randomness, again this would need some surrounding story development.
• Special challenges unlocked after beating Nolock and getting a large enough amount of points