head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Optimization · Grand Arena
Asymmetric sci-fi RTS where tiberium economy management and faction counter-play are the decisive layers.

Execution · Practiced Mastery
A basketball sim testing shot timing and tactical play against opponents.
Command & Conquer: Tiberian Sun leans Optimization (Grand Arena); NBA 2K3 leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer: Tiberian Sun
Stealth unit deployment and artillery positioning need precise timing
NBA 2K3
Shooting and dribble timing decide plays
Command & Conquer: Tiberian Sun leans a little harder on reads, though the gap is small.
Command & Conquer: Tiberian Sun
NOD vs GDI asymmetry means opponent strategy must be predicted
NBA 2K3
Human opponents reward reading offense and defense
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer: Tiberian Sun
Tiberium field growth and map elevation create meaningful uncertainty
NBA 2K3
Shot success carries randomness
Command & Conquer: Tiberian Sun leans a little harder on optimization, though the gap is small.
Command & Conquer: Tiberian Sun
Harvester routing and unit counter choices are deeply solvable
NBA 2K3
Playcalling, rotations, and team management reward planning
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.