When you open a new file, depending on whether you have the grid visibility on or off, Houdini uses a different zoom level for the new scene.

Is this by design?

To try:

1. Turn on the grid
2. File -> New
3. Remember how close the grid looks

then

4. Turn off the grid
5. File -> New
6. Turn on the grid

You will see that the grid is now much closer, instead of being framed as a whole in the first example.

What do you guys think?

Houdini homes the view on the perspective grid. If it's not visible it homes on the origin gnomon/world center coordinates (0,0,0) .

Turn on the grid with nothing in the scene and toggle between zoom for home (space-h) and gnomon center (space-g) and you will see it is by design.