As this is a legacy port, perfection is difficult. Please note the following:
There are two primary sources for firmware: the official stock firmware from your device's manufacturer and the vibrant world of community-developed custom ROMs. rk3188 android 51 firmware exclusive
The 30% performance uplift comes from better kernel scheduling and the exclusive "SmallTask" governor, which keeps the A9 cores from parking prematurely. As this is a legacy port, perfection is difficult