OROCHIMARU was looking for the perfect host , Kimimaro was ORO next vessel if it wasnt for his unknown sickness he would be perfect...
Now i believe[ only my opinion ] that OROCHIMARU wanted KIMIMARO's body for the mere reason that KIMIMARO's clan "The KAGUYA" was distant relative of the younger son of the sage of the six paths... This really sounds redundant and absurd but this what i had in mind :
SAGE OF SIX PATHS has two sons the OLDER son[ the eyes ] and the YOUNGER son[ the body ]
RINNEGAN - SHARINGAN - BYAKUGAN -----> these are the EYES
SENJU - UZUMAKI - KAGUYA ---------> these are all what i BELIEVE to be the BODY
It may sound so Far fetch but really who knows if OROCHIMARU wanted sasuke body because of its sharingan .. Maybe
this would make sense why he really wanted KAMIMARO KAGUYA's body because he was a distant relative with the young son of the sage plus the KEKKEI GENKAI it would be perfect...
:D :D :D