It seemed to me that the belly was the best spot for a strobe if the goal was pilot's visibility. I used a 3D printed bracket that clips into the battery vent slots. I'd say not much occlusion of the slots based on what I can see. I flew in -5C weather the other day, so not much of a test of battery overheating. In summertime, MMMV.
No effect on flight characteristics other than tremendously improved visibility. Firehouse "V" with five incredibly bright strobes.
With the strobe mounted, you can't use the DJI-supplied propeller protection bracket. This was my temp solution.
As mentioned previously, the strobe renders the stock landing gear irrelevant. Since I hand launch and catch 100% of the time (it's winter!) it doesn't matter. Strobe has no apparent effect on hand catch landing.
Once I realized that I didn't require a NASA-qualified heavy Velcro compression, I found that it's effortless to remove the strobe, in which case the prop protection bracket works perfectly.
This shot was taken at just under the 400ft altitude limitation. Previously, the Mini would have been invisible at that height. With the strobe, effortless. Goes a long way towards anxiety reduction.