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
A four-player Wii Kirby romp gathering ship parts for the stranded alien Magolor.

Optimization · Practiced Mastery
A relaxed collect-athon testing character-ability matching far more than any skill ceiling.
Kirby's Return to Dream Land leans Optimization (Practiced Mastery); LEGO Batman 2: DC Super Heroes 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.
Kirby's Return to Dream Land
Easygoing main game; EX mode adds modest demands
LEGO Batman 2: DC Super Heroes
Button-mashing combat designed for children's hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Return to Dream Land
Bosses are pattern-scripted
LEGO Batman 2: DC Super Heroes
Enemies are harmless scripted waves
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Return to Dream Land
Energy sphere hiding spots are static secrets
LEGO Batman 2: DC Super Heroes
Stud and minikit locations are fixed once known
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Return to Dream Land
Super ability timing and sphere collection are solvable
LEGO Batman 2: DC Super Heroes
Matching character abilities to gated collectibles
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.