A recent exchange running through a couple of other blogs I follow led me to check out the back catalog of Spells and Steel, a blog focusing on developing a version of Basic D&D that's informed by facts and experience with medieval combat.
What I like about Charles Taylor's approach: he's intent on keeping the simplicity of Basic D&D throughout, resulting in a very boiled-down system that still relies mainly on d20 hit, d6 damage logic. So, multiple opponents are tough, trained fighters have a huge advantage in ability versus civilians, skill and not hit points helps heroes survive, etc. Although my house-rules don't kill nearly the same amount of sacred cows, I do appreciate the impulse to consult reality instead of received "game" logic.
One observation of his that I want to put into my own rules: outside of the movies, combat with weapons actually takes place at about a 10' distance heel to heel, with combatants stepping in to attack. So a zone of attack should look more like the right picture than the left:
This means that the situation on the left should then represent close and brawling combat, where longer weapons would be less effective. Closing to a 1 space distance would require some disadvantage, like taking a hit attempt on you and failing to close if it hits.
I already have rules for that but they stick to the example of the Metagaming Melee game, where you actually moved one counter into another's space. Apart from realism, the benefit when playing with figures on a grid (as I do) is that you don't have to jam figures into the same space to represent a brawl. Just say that if one figure is facing another and adjacent, it's brawling with the other guy.