I went into creative and did quite a bit of testing how the material properties affect arrow weight, damage and accuracy.
I found that rods and fletching are only weight/accuracy modifiers, and that slime comes out on top for rods with feather being the superior fletching material in all instances. (we all knew this already didn't we?)
you can group the arrowheads into 5 groups with increasing damage
Slime,wood and paper arrowheads are very light, with slime coming in at only 0,55 and paper being the heaviest at 0,68 with an extra modifier added, however i doubt that this is actually worth it considering the dinky base damage of 1,5.
bone,stone and netherrack all give a base damage of 2. with bone being the lightest at 0,6. so early game you are better off using bone if you don't have flint or cactus. (not a likely scenario tbh) stay away from stone and netherrack. they are fairly heavy at 0,96 and 1,16 respectively, and they do not give any sort of functional advantage despite being stonebound.
the biggest group is the 2,5 base damage group. this is where you find steel, flint,cactus,thaumium,bronze,copper and iron.
Cactus is the lightest arrowhead in this class, and combined with a slime rod and feather fletching it gives an arrow of mass 0,62
the main thing here, is that you can make these without first getting the smeltery up and running.
The outlier is the thaumium arrowhead, since it gives you an extra modifier at the cost of increasing the weight to 0,82
Obsidian is the third best material, but it requires the smeltery, making flint the second best material overall for arrowheads early game prior to smeltery.
Ardite,alumite,steel and cobalt give a base damage of 3, but are very heavy, with alumite being the best with 1,4 and cobalt being the worst at 2,25
The real heavy hitter is manyullyn, and heavy is the keyword. the weight is 2,59, and the base damage is 3,5.
A special note on the thaumium paper feather based arrow. it gives 2 extra modifier slots at the cost of increasing weight to 1,5 and reducing accuracy to 62,66%. When using this arrow it is possible to get a base damage of 10,5 even before you add on the modifier adding diamond/netherstar thing by just adding a LOT of netherquarts.
So as far as maxing out damage is concerned, this is the arrow to go to if you feel ultra rich. it should one shot most anything this side of the dragon and wither.
The following modifiers are confirmed to not be available for modifying arrows: Lapis,redstone,silky,piston.
Then there is some modifiers that require some more testing:
Lava crystal - does this actually do anything for arrows? it does not auto cook meat, and it does not seem to add any damage.
moss - likewise, is there any point at all?
wither bone - can anyone else confirm life steal working with arrows? my testing is indicative of this working, and is therefore a pretty good modifier to use when available.
obsidian + ender pearl - beheading - unconfirmed, but very good if it does. wither skellies are a pita due to the wither effect. being able to cheeze them off at a distance would be really nice.
these I am certain do work:
consecrated soil (smite)
Fermented eye (arthropods bane)
Nether quarts (extra damage)
blaze powder - burn baby burn- the pyromaniacs favorite. it also cooks dinner. one of the best things to add imho.
Bow modifiers:
Lapis - I havent tested enough to confirm
piston - knockback works, but is weak unless you add all 10 pistons to fill up the modifier slot. it then becomes about as good as an unmodified hammer.
redstone - we all know what this does.
emerald/diamond - more durability
moss - durability regen (my fav modifier for bows. they never break with this on)
obsidian plate - adds reinforced
consecrated soil - smite - unverified
fermented spider eye - arthropods bane - unverified
nether quarts - does nothing - confirmed in testing.
lava crystal - no effect - needs independent verification tho.
cant be added:
blaze powder
obsidian + ender pearl
sorry if this wall'o'text passed someone elses replies. it took a while to write and verify it.