Sandra,
FIrst of all it is VERY important to understand that changing the depth, max children and max routers will render your solution NON-COMPLIANT and you will not be able to:
1. Connect to certified products
2. Certify a public profile, but only as an MSP.
you must calculate that the biggest address used by the CSKIP address does not surpase the 16 bit integer used for the address.
For changing(increasing) the depth you also change(lower ) the maximum number of children and maximum number of routers.
As increasing the depth will lower the size of how many children a router has the memory impact will not be increased.
BR,
Mads