Any assembly can be cut into pieces. Advantage, one can change/ improve a module at its convenience.
The best system (in my opinion) is a board with main functions and a bus with several connectors (Like a pc)
Then you will be free to modify (for example, there was a lot of discussion on the AGC) --> It's will be and addon near the audio module.
Provide in this case an interconnexion by jumper on the mother board.
There’s a lot to think about interconnexions...and others, ex:1 or 2 free slots also for personal fabrications, etc.
In short, this is no small matter.
But if you want to cut out a Ubitx, is that allowed? Only the author can tell you.