The only other thing i believe elevation should play a part in, is that the character in the lower elevation should suffer accuracy penalties on attacks at characters in higher elevations.
Good form and practice overcomes accuracy penalties from both low and high ground. The first time you practice shooing from an elevated or lower position you'll probably shoot high with each. With practice you can be as accurate shooting uphill or very close to shooting on level terrain. With practice and good form you can be more accurate from an elevated position than level ground, maybe because less arc idk really know why. However I still struggle with good form shooting at a steep downward angle as maintaining the 'perfect T" and only bending at the waist is tough (for an older guy) but those shots are rare in reality. Damage is less from low ground and more from elevated ground IRL. Gravity really plays a surprising factor in projectile speed.
There are a lot of factors to consider in all of this. So we can only try to play the factors as evenly as its two identical shooters in skill and weaponry, the only difference is that one is elevated on a platform and the other is ground level. There's no denying that the elevated shooter will gain the better lay of the land compared to the ground shooter. So when it comes to "accuracy" specifically, there's no real gain or loss in either position. But if it were the heat of battle and both shooters had the intent to launch an arrow thru the other's body. One shooter has an active look at the others full lay of land, while the other can only see the one spot where the shooter may or may not shoot from.
I guess imagine it like bird watching. Is it easier to maintain "focus" on a bird hopping around on the ground from bush to bush while you are above it, or when you are on the ground and it's hopping from tree to tree.
Again lots of minor factors to weigh on. Let's hope we can find a solid shared opinion haha.
