That a good rule to use to think about this. Would a Human DM allow it.
I expect most DM would veto stuff like
Acid Slash leaving a puddles of acid ( rules state you can target 2 people if within 5 feet )
Firebolt setting the floor on fire ( nothing about clothes catching on fire or extra effects. )
Ray of Frost making a patch of ice ( rules state speed reduce by 10 feet for a round )
etc.
I been looking through the books and can not find any arrows like what are in BG3.
There is
Alchemist's Fire (flask)
Type: Adventuring Gear Cost: 50 gp Weight: 1 lb
This sticky, adhesive fluid ignites when exposed to air. As an action, you can throw this flask up to 20 feet, shattering it on impact. Make a ranged attack against a creature or object, treating the alchemist's fire as an improvised weapon. On a hit, the target takes 1d4 fire damage at the start of each of its turns. A creature can end this damage by using its action to make a DC 10 Dexterity check to extinguish the flames.
Notice no puddle of fire and if anything was going to leave a pool of fire, you would think it would be Alchemist's Fire (flask)
I expect the elemental arrows should be like that, hit you with an extra 1d4 elemental dot for a few rounds, not better then many spells.
