head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Practiced Mastery
An open-world crime game where managing a criminal empire's territory is the deeper system.

Optimization · Practiced Mastery
A WWII stealth game about ghosting through guard patrols as a British spy.
The Godfather II leans Optimization (Practiced Mastery); Velvet Assassin leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
The Godfather II
shooting and brawling need moderate skill
Velvet Assassin
Stealth kill timing and shadow movement
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
The Godfather II
scripted rival families, no adaptation
Velvet Assassin
Guards patrol on fixed scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
The Godfather II
territory events and drops vary
Velvet Assassin
Patrol layouts unknown only on first attempt
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
The Godfather II
empire management and territory control solvable
Velvet Assassin
Routes through guard patterns are the solvable core
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.