I wouldn't reason too much over it (or other game-defined conditions) because otherwise you'll start getting reasonable arguments from your players about changing when/how conditions should work, usually to their advantage. I would just apply it only when the game says so (although things such as cover are always at least partially subjective).
Seeing how archers get the short end of the stick in 3E and 3.5 (how's that in Conan, WB?),...
....I'd try and make it easy for them to shoot into melee as much as possible.
...A chance to hit an ally, even if the chance is small, will deter that whole fighting style.
Or promote the Precise Shot Feat!
Why do you say archers are hampered? Because ROF is reduced per round from previous editions of D&D?

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.