I think we will try this. I know that my players feel like they have no impact on what happens when a Horde attacks them, to their annoyance.

It is not because they might get damaged, but simply because they just get told "you're hit for X dmg". They just want to feel a bit more in control.

I have been trying to work on ideas for improving the Horde system in general as I still feel it is very "rough" around the edges, but haven't found the holy grail to do it yet..

I've been using it for quite a few sessions and players appreciate having the ability. Against large hordes it gives a small chance which is still better than nothing. And there are tangible benefits to smashing and weakening a horde.