My current thinking is that the most straight-forward is just a flat 1% house edge on all bets.
Innovative!
When players do well and win money, there will be a glut of valor on the market (and no new silver) so I expect the house edge will be rather closer to 1%.
That's only the case if the winning players insist of selling their valor instantly even though the price is low. A smart player (yeah, I know) would wait for others to lose, increasing the supply of silver, and bolstering the demand for valor. In the long run the price should return to 0.5 bits per valor, if not more, and so the house edge for the patient player should be no more than 0.5%.
And when players lose money, there will be a glut of silver on the market (investors wanting to realize their profits) so the silver be worth more and the house edge will be closer to 0%.
Similarly smart investors will be unwilling to part with their silver too cheaply, understanding that demand for silver will pick up when it becomes rarer than valor.
Smart traders I imagine will want to take advantage of this and "time arbitrage" the value of silver and valor to ~0.5 bits.
So it would be +EV to buy any silver or valor that is on sale below 0.4 bits, with a view to selling it at 0.5 bits later. That makes sense.
My hope is it'll be a fun little ecosystem
Will there be an exchange built in to the game site?