Broad heads and bodkins
Historically, archers would have a quiver for each type, meant for their opponents who could range from knights to lightly armored cavalry.
It would be cool if you put a third arrow option that has half the total number of each – with an option to just switch in between them by clicking a button
This is similar idea behind fire arrows if they were implemented. Pushing a button jammed on an oil soaked sponge (wool?) on the end of the arrow which the archer then lit. Long reload time but you have a fire arrow. And can do that 3-5 times depending on the bow.
Having a split between arrows might be a little bit OP. Maybe make it so its not a 50 50 split. But more a 20 80 split or similar. I understand historically where your coming from. But making archers too versatile isn bad thing for balance. In real life fuck balance.
There was a medieval painting of a crusade where the Arabic archers had 3 quivers. One for barbed arrows maybe?