I designed this to be pretty similar to your typical breadboard. it has:
- Strips of 5 holes
- Center channels for ICs
- Two 'breadboard' patterns
- Two buses along each edge, 4 per breadboard
- 48 rows
- M2 mounting holes
- Mounting hole dimensions printed on board
- 2,54 mm pitch
I also made the channel between the two 'breadboard' patterns large enough that you can safely cut the board in half.