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

Optimization · Systems & Chaos
A freemium town builder testing patience and timer scheduling more than any skill.

Optimization · Pure Optimization
A heartfelt WWI puzzle adventure following four lives through the trenches.
The Simpsons: Tapped Out leans Optimization (Systems & Chaos); Valiant Hearts: The Great War leans Optimization (Pure Optimization).
Valiant Hearts: The Great War leans a little harder on execution, though the gap is small.
The Simpsons: Tapped Out
Tapping buildings has no skill component
Valiant Hearts: The Great War
Gentle timing in a few chase sequences
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
The Simpsons: Tapped Out
No opponent in a solo town builder
Valiant Hearts: The Great War
No opponent
The Simpsons: Tapped Out leans a little harder on variance, though the gap is small.
The Simpsons: Tapped Out
Event prize rolls add mild randomness
Valiant Hearts: The Great War
Fixed puzzles, fully visible
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
The Simpsons: Tapped Out
Task scheduling and payout timing are the only decisions
Valiant Hearts: The Great War
Simple inventory and environmental puzzles with set solutions
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.