Special feats like stand still/awesome blow(
srd mont feat)/driving attack(PH 2) allow you to stop foes or drive them back, trip locks them down. All have special requirements as is necessary and sensible, just cause your stick is bigged doesn't mean you can automatically keep things at bay.
Popping that can of worms you may as well go back to 1st edition that had weapon reach and initiative type rules. but under 3.5 what would you sensibly rule ? Whats the logical conclusion? If long spears keep long swords at bay, long swords should keed short swords at bay and they all trump daggers. Next players will be making long swords with 1-2 extra inches on the end (rennasance and musashi stylez), the big creatures with reach just become sillyer etc etc.
Some gems for reach:
5ft step
Tumble away (and have an attack item.. or a wand storing weapon from dungeon scape I think)
Monk dip
Armour Spikes + 2wpn fighting
Dust of Dissapearance
Sorcerer (true strike/feather fall) dip to dragon disciple for claw/bite and other goodies (also good as a archer even if unlike monk archers melle is not auto scaling in effectiveness)
Scout (move first and wait for the beef)
Spring Attack
Short Haft (PH 2): change reach to 5ft or wpns that have both are: Kusari Gamma (
DMG)/Spiked Chain/Great Axe(complete adventurer i think)
Deft Opportunist (complete adventurer): +4 to hit on opp attks
Expert Tactician (complete adventurer): +2hit/dam on opponent opp. attacked for 1rnd for everyone.{great for party helping}
Standard of Courage (complete warrior): put on a reach weapon, 30ft rad = +2 morale bonus to hit and damage and saves.
... The last 2 in unison make ANYONE a bard... alas I love them so, but they suck n they die !!
Reach is a great way to make the non BAB full classes comparable in melle awesome!