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

Optimization · Pure Optimization
Managing a coin economy against escalating scripted raids with deliberately unexplained rules.

Optimization · Pure Optimization
Minimalist transit puzzle; route topology under spawning pressure.
Kingdom: Classic leans Optimization (Pure Optimization); Mini Metro leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Kingdom: Classic
Riding left and right and dropping coins demands no twitch skill
Mini Metro
light real-time line-drawing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Kingdom: Classic
Greed waves follow scripted escalation, never adapt to you
Mini Metro
no adversary
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Kingdom: Classic
Unexplained mechanics and map layout are hidden until mapped
Mini Metro
station spawn pattern
Mini Metro leans a little harder on optimization, though the gap is small.
Kingdom: Classic
Coin economy and wall timing are the solvable core
Mini Metro
line topology and routing
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.