Rainbows are seasonally appropriate for every season! They never go out of style.
Normally I'd scream overkill at a cake this busy but there is some amazing balance going on here. A striped rainbow heart inside a striped rainbow cake? A rainbow of fondant sprinkles so perfect they must have been placed there by very patient elves? I swoon for this kind of overkill.
Admit it, you've still got a few candy canes hanging around. You're feeling a little guilty because you know you shouldn't eat them but you don't want to save some old cheap candy until next year. Go ahead, garnish some pancakes with them. I won't tell.