I do not make .deb packages. I also do not use make -jx, or make modules.
Pretty much I do make menuconfig, make, make modules_install, make install.
In menuconfig I change things to what I want, like 4k PAGESIZE, and for my system with 2x8 cores, I use 64 processors.
If I want I use mc (midnight commander) as root or sudo to look at /boot and perhaps remove,move, or add kernels and
other stuff and then use update-grub as necessary.
Using the update-grub command may require you to login as su - (the - is important) and then do /usr/sbin/update-grub.