Oppositely, I use Perception for something (tiny) that's difficult to spot (or sense more broadly) while I use Investigation for that which is trivial to perceive but requires analytical provess to deduce any deeper meaning from, e.g., to notice that the books on that shelf seem off (the bookshelf itself being in plain sight).
Dungeon Dudes dedicated an entire video to the topic where they emphasize that the players need to elaborate on how they're looking instead of just saying "I perceive the room" or "I investigate the room": https://youtu.be/ZY32CT4VaLQ
Thor
2024-01-11 19:58:17 +0000 UTC
Personally, I have always understood that scale was the differentiator between perception and investigation. Want to notice that guy sneaking over there? Perception. Want to notice that the books on that shelf seem off somehow? Perception. Want to notice that there is a minute crack in the wall where a secret door is? Investigation. Want to notice that someone hid a sheet of parchment in that dusty tome? Investigation, unless you're reading the book, then no check required.
Don
2024-01-11 08:36:07 +0000 UTC
Great video
The only thing wrong with switching from athletics/acrobatics to strength/dexterity for grappling/defending is picking up a skill is cheaper than getting profiency in an additional saving throw