Not a good idea!
Proper matching of the recoil spring weight to the weight of the slide and caliber of ammo is essential to proper operation of the gun and is built into the design. A change of 1 lb. more or less on the recoil spring might not hinder proper operation but would be negligible in the effort required to rack the slide. More than that; there are a lot of reasons not to do it.
I've seen a change in technique help with folks who have this trouble and maybe that will work for your wife.