melee weapons to use DEX thac0 bonus

So I have a thought that some melee weapons would be better off using DEX for thac0 bonuses instead of STR: daggers, short swords, rappers, maybe even scimitars - basically, thieves' weapons. And I figured I could do this in NI pretty simply, by changing them into very very short-range missile weapons, using the melee attack animation, and applying a -4 AC bonus against melee to offset the usual penalty for holding a ranged weapon when being attacked in close range.

Before I set off to change every such item individually, has this been done before? Are there any pitfalls to this approach that I'm not seeing? Any more experienced modders have any input?