You have the answer: a lush, sweet system in one room and a dry, analytical one in the other room. When the dry system starts to get on your nerves, you switch systems for a day or two. My sodium intake can fluctuate and when it's higher my tinnitus is higher and it makes the crisper sounding system temporarily unbearable.
I have my two setup like this, McIntosh with Vandersteen and Mofi Sourcepoint in the LR, Harmon Kardon 330c and Ohm Walsh 2 in the BR. Some days only the HK will do.