Teh your are doing something wrong
Without any quests on a fresh acc u can get a perfectly 50/50 balance once an acc hits 44 RC.
If you put all cata runes on top it should be fine ^^
I was having similar issues with the newest java 8 version
I downgraded to java8_291 and that seemed to work the most stable, especially for mirror mode!
You can still find the version in the archive of oracle if you google it