Not actually ridden a Z1000SX but I did test ride a first gen Z1000. I have also owned several Vstrom that have the same engine as your SV and test rode a SV1000
The Kawasaki is a great bike that would be a different experience to the SV. Instead on the torquey v twin the inline Four has less low down grunt but the mid to high end rush is intoxicating.
I found the Z1000 to be vibey but not to bad enough to put me off. A real fun ride
Part of Motorcycle ownership is changing your bike every so often because they are so varied. I'd say go for it
I ride a Suzuki GSX1400 now as it gives good compromise between comfort and grunt