Ummm the more Agility the more faster the swing is
 

Uhhhhh Read the title

The Dex and Strength of you character affects the Speed of your character, both walking and weapon speed.

Ok... I think I should say... the current weapon speed system is kind of inverted... currently it is the heavier you are... the faster you swing... It should be.... the lighter you are... the faster you swing...

And my sudgestion...
Weapons can either be considered Light, Medium, or Heavy
Light weapons and Range weapons use a Dexterity for damage increases and WC/weapon speed increases.
Medium weapons and spears should use Strength for damage and Dexterity for WC/weapon speed increases.
Heavy weapons should use Strength for both Damage and WC/weapon speed

and agility exp determins how much better you can do agility based skill such as stealing, or disarming traps