I'd be asking what characteristics it messes up.

For certian, the following will be effected:

The following will be lesser or lighter:

Total weight
Length
Swingweight
MOI
The lie angle will get dynamically flatter (unless you bend over more).

The following will be unaffected:

Loft


Swingweight/MOI can be increased by adding weight back to the head, and total weight can be increased by adding weight anywhere.

I tell you, if your putter fits your posture better, you'll start dropping more putts and you'll care less about the characteristics!