Maybe the most boring part of the build would be the router bed.
But although it's boring, it's a very important part, it would be useless without it.
The router bed is the place where you place the part that needs machining.
Therefor the surface needs to be flat, and perpendicular to the endmill to ensure good result in your work.
Also there should be some sort of method to secure the workpiece.
The best way to go would be an aluminum t-slot table, but that would be way too expensive for me.
So the first try would just be MDF board, with holes... And in the first modification you can see some t-track.
The top surface should be something you can resurface, and is called the spoil-board.