Whether replacing or as a toggle option alongside the current 16 I don't mind, but here's my argument:
It's the lowest number divisible not just by the current 4, 8, and 16, but importantly, 6, 12, and 24, too, alowing for proper hexagonal and equilateral triangle building. Not to mention the fine tuning and nearer-circles available with thrice as many divisions.
Why hexagons? Bestagons.
I'm aware mods cover this, but after activating and deactivating my 60+ mods one by one and restarting the game each time to figure out which one was preventing loading into the world (it was the one that allowed holding left click instead of spamming to attack, NOT ANY OF THE MODS INVOLVED WITH LOADING OR WORLD GENERATION. What??? Why???), I argue for vanilla inclusion to prevent the feature potentially breaking with each update.
Also combine the angled beams into a single object that can be rotated by toggle on the Z plane, but that's another post.
Source: https://www.reddit.com/r/valheim/comments/tyfnkv/petition_for_48_rotation_divisions/