Well...
1. It might just happen that sometime in the future, the current limit to WIL of Level 80 will be extended -as has happened recently to STR, AGI, INT and END.
2. There are potions that can give a temporary boost to your Stats.
3. There are also weapons which can boost a Stat when you equip them.
So, equip a weapon that needs a higher level of WIL in one hand and equip a weapon that gives you a boost in WIL in the other hand!
