Destructible environments in current Toribash, in the same manner as Sumotori, don't exist probably because the game has used the same engine for 12 years and would shit itself at the first sight of a fracturable plane of matter - however on a new, reworked and more stable engine I could easily see it happening. The ability to have it as a setting for an object you can place (while creating a mod) much like making it static or not, and a threshold for how much it can take before cracking.
Since this is being done in Unity3D as well, I'd imagine there will be far more amazing mods that will be able to be created with a new stable game (having mucked around in Unity3D myself for a while, I can vouch and say it can handle shit real well).
Aside from that, good luck dev team, and godspeed with this new project of yours.