head to head
Portal asks more than Mario's Super Picross, and the gap is execution.

Optimization · Pure Optimization
Pure logical deduction - each nonogram is fully solvable from its number clues.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Mario's Super Picross leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Mario's Super Picross
Marking cells has no speed pressure worth naming
Portal
Portal placement timing modest.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Mario's Super Picross
A logic grid cannot adapt to you
Portal
No adversary modeling player.
Mario's Super Picross leans a little harder on variance, though the gap is small.
Mario's Super Picross
The hidden picture is fully derivable from the clues
Portal
Deterministic chambers; no randomness.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Mario's Super Picross
Pure logical deduction - every puzzle is literally solvable
Portal
Pure puzzle-solving optimization.
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.