if your wife finds the hotspot distracting, isn't that just another way of her saying that the hotspot is too bright for her? maybe she just needs to dial down the brightness a little bit. i've done some, not a lot, but some running on trails, some of them pretty nasty, and honestly, i don't think i've ever felt like i needed more than 50 lumens. anything more than that is just too blindingly bright.
if not, using some diffusion material on the lens might help, but at the same time, diffusion material can drastically change the look of the beam and she may not like the result. the best way to test out whether you'll like it is to try scotch tape, as the effect will be similar to what you find with better diffusion materials.
the best way to preserve the look of the beam as much as possible while still diminishing the hotspot is to mist a fine coat of hairspray (1) or clear acrylic spray paint (2) onto the reflector. this will result in an almost totally even disk of light with a hard edge and a bright spill similar to a regular beam. but this also requires you to remove your reflector and risk damaging it. it's only recommended for certain lights and for experienced hands.
(1) this can be washed off
(2) this cannot be washed off