head to head
Hardware: Rivals asks more than Wii Sports Resort, and the gap is reads.

Execution · Competitive PvP
Vehicular arena duels of handling and aim against human drivers.

Execution · Pure Mechanics
Island-themed collection of twelve motion-controlled sports showcasing the Wii MotionPlus accessory.
Hardware: Rivals leans Execution (Competitive PvP); Wii Sports Resort leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Hardware: Rivals
Vehicle handling and turret aim decide most duels
Wii Sports Resort
MotionPlus precision in swordplay, archery and bowling
Hardware: Rivals leans clearly harder on reads.
Hardware: Rivals
Human opponents' arena rotations reward some prediction
Wii Sports Resort
Local versus duels involve mild feinting
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Hardware: Rivals
Pickup spawns add mild positional randomness
Wii Sports Resort
Slight physics and CPU pattern randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Hardware: Rivals
Weapon-pickup control and map knowledge underpin wins
Wii Sports Resort
Each event has small learnable technique optima
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.