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

Optimization · Pure Optimization
A chaotic comedy adventure whose elaborate multi-step puzzles test patience with absurd causal chains.

Optimization · Pure Optimization
Pure logical deduction - each nonogram is fully solvable from its number clues.
Deponia leans Optimization (Pure Optimization); Mario's Super Picross 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.
Deponia
Point-and-click with no timing elements
Mario's Super Picross
Marking cells has no speed pressure worth naming
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Deponia
Comedy adventure with scripted characters throughout
Mario's Super Picross
A logic grid cannot adapt to you
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Deponia
Deterministic puzzle world with fixed solutions
Mario's Super Picross
The hidden picture is fully derivable from the clues
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Deponia
Convoluted Rube Goldberg puzzle chains demand careful causal mapping
Mario's Super Picross
Pure logical deduction - every puzzle is literally solvable
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.