Optimize boot time in Xavier NX

I want to reduce the boot time of the Jetson Xavier NX from 49 seconds to about 25 seconds. So far, I have managed to reduce it to 31 seconds. The steps I have taken include disabling some services in rootfs (using the systemctl command), skipping wait time in the bootloader, reducing log output by modifying /boot/extlinux/extlinux.conf, and removing some .ko files in /lib/modules. Now, I am not sure how to proceed. Does anyone have any helpful ideas? Thanks.