Consider reversing the air-flow of the BB3 enclosure.

[fietser28]

Currently the fan of the BB3 pushes the air from the back to the front/top/side air vents.

If modules produce heat (for example an electronic load) and have vents on the front panel then warm or even hot air will blow in the direction of the user. This will be uncomfortable for hands during operation of the BB3.

I assume reversing is a matter of reversing the physical mounting of the fan and has no downsides to the rest of the system, but it should be tested.