Great little project, Eric.
Yes, a wider "footprint" would help with stability. And you can get some pretty long "carriage bolts". Some varieties only have the last inch threaded, with the rest being just round rod. And they have that domed head on them.
There is a little soft-cover book that was put out by Western Horseman magazine called Horseman's Scrapbook: Helpful Hints for Horsemen by Randy Steffen isbn 0-911647-07-4 published in 1986. It has a lot of "hints" of things to do to re-use horseshoes. Things like hinges, coathooks, andirons, gate latches, etc. Even mailbox stands, boot scrapers, and whole chairs.
Fun little project.
Mikey - yee ol' grumpy German blacksmith out in the Hinterlands
"Man will never be free until the last king is strangled with the entrails of the last priest."
- Denis Diderot (1713-1784)