I don’t know of any way to use apt/dpkg tools directly on the host for an independent package system not part of the host. Sorry.
dd speed is only limited by the SD card speed, though options may speed it up. The “block size” argument (for example, “bs=512” for half a kbyte) can be increased and buffering within the host PC will likely improve performance (not all devices work well with larger block sizes, but SD cards do). So for example, compare “bs=512” and “bs=1M” (1 Mbyte). Perhaps even “bs=10M”.
Btw, if you have a master image from an SD card, then you don’t read again from the SD. You perform your SD writes from reading that image off of a fast PC hard drive/SSD. Don’t copy directly from one SD to another, copy SD1->PC->SD2.