The two holes in the back of the smart are strong enough to hold a pretty heavy bike/ski rack. Which unfortunately is about $500 and backordered to infinity. What other things could we use those holes for?
I have an idea. Make a 1 1/4" receiver that hung down at normal tow level and bolted into the holes. Not to use for towing, absolutely not, but to be able to use the many accessories already made to fit in a 1 1/4" receiver. I have seen bike racks, ski racks, coolers, cargo holders made to fit in a 1 1/4" receiver. One of those cargo holders would be a great place to hold a spare and jack for a long trip.
It may have to be triangulated by a support running from the back of the receiver to the frame somewhere, but I'm guessing this wouldn't be that big a deal to figure out.
The whole world of standard 1 1/4" accessories would be opened up.