I have a couple Mouse and have played with a Deep 4 30". Love both, yet was bothered by the weak tone of the low E on the Mouse as compared to the Deep 30"
Thinner body = less tension on the E
Solution:
#8 brass washers to the rescue ... 5 or 6 washers on the ball end of the E string
and 2 on the D string to balance all 4 strings ... this has transformed the Mouse.