I am not an expert, and the whole issue of LDLP is still under discussion basically due to the many different methods of measuring it (
NMR seems to be the more accepted).
It seams that if you has been treated with post menopause hormone therapy then LDLP can signal risks not determined by normal LDL levels.
However after what I have read, I tend to agree with your position of increasing the Simvastatin, not because avoiding a new med, but because it seems more effective to reduce LDLP.