Fees on profit make much more sense to me than transaction fees - transaction fees may make otherwise sensible trades unprofitable (e.g. if my math is correct, if a market's "true" probability is 2% and it sits at 1%, current transaction fees are larger than possible profit from correcting it)

If anyone can figure out a better way to create an LVT in manifold I'm open to it.

Taxing "land-like" assets—scarce, essential for gameplay, and varying in value based on "location" or strategic importance. Unlike physical land, virtual assets that fit these criteria could include unique or limited items, strategic positions, or essential resources. Taxing these assets encourages active and productive use rather than speculation or hoarding, aligning with Georgist incentives for efficient resource allocation.

If you can find a way to implement an LVT in Manifold, I'd vote for that