This is a rework to make fighters a little interesting. It focuses on improving their utility compared to other martial classes, and on giving them a way to "spend" their excess THAC0. At high levels when a fighter with a THAC0 or 5 is hitting almost everything he fights, special combat maneuvers give them a way to control the battlefield in a way that other classes cannot.
At level 1, fighters gain a free weapon specialization in one of their proficiencies. The fighter gains a +1 bonus to all his attack rolls with that weapon and a +2 bonus to all damage rolls (in addition to bonuses for Strength and magic). The attack bonuses are not magical and do not enable the character to affect a creature that can be injured only by magical weapons. Specialists also gain additional attacks per round, as documented in the PHB.
Specialists in ranged weapons gain an additional range category: point blank. Point-blank range for bows is from six feet to 30 feet. Point-blank range for crossbows is from six feet to 60 feet. At point-blank range, the character gains a +2 modifier on attack rolls. No additional damage is caused, but Strength (for bows) and magical bonuses apply. Furthermore, if the character has an arrow nocked and drawn, or a bolt loaded and cocked, and has his target in sight, he can fire at the beginning of the round before any initiative rolls are made.
Those who are specialised in a ranged weapon may suffer a -4 penalty to-hit in order to fire into an engagement without a risk of harming allies as long as the engagement is not being fought at closer-quarters than a short sword. For example, this would be possible for two warriors dueling with blades, but not for two men grappling, two thieves fighting with daggers or a warrior fighting a giant spider. When in doubt, the DM's adjudication should be called for. On a roll of a natural 1, the archer should reroll their shot as if made against one of their allies in the engagement.
Finally, warriors who are able to find skilled trainers - either through expenditure of resources or by undertaking quests - can progress their specialization and become weapon masters. This will improve the effects of specialization further.
From 3rd level, a fighter gains extra attacks when fighting multiple enemies who are significantly weaker than him. The extra attack(s) can't be used on the same enemy, they have to be spread out amongst their opponents. For every 3 levels or hit dice his opponents are below him, the fighter gains one additional attack. Creatures with less than 1 hit die, such as goblins, are considered to be level 0 for the purposes of this calculation.
For example, say that a level 9 fighter is fighting some 0 HD goblins; he is 9 levels above them. This means he gets up to 3 extra attacks against them, though he can only use them all if he's fighting at least 4 of them.
From 10th level onwards, fighters can use their weapon proficiency slots to buy high-level abilities which confer exceptional martial powers.