The animus geodes are far too fragile to serve as a permanent solution. If jostled or dropped with a soul locked inside, they crack and flake until they shatter. A sharp blow turns them to dust!
You've complained about their price, so I must wonder how much you paid for these things. If anyone tried to sell me something this hard to acquire, incredibly expensive, and exceptionally fragile, I'd bleach his bones and make him my skeletal footstool.
I would never criticize your wisdom, but you must consider the best use of our gold. "Complete lack of scholarship on the subject" does not mean "lost Ayleid secrets from the First Era." I don't know if the fragility comes from how we're using the animus geodes, if it's inherent to their structure, or if this is simply a bad batch.
I can only hope that the "great treasure" in Stillrise Village proves a wise investment.