Seeing as Basil is stocked with many recipes readily available in the Hall of Heroes, why not make it so that every recipe available in the hall of heroes is priced 10% less at Clockwork Terminals?
I can see players bumping the prices up 5% on the market and selling general-use recipes at a profit. 10% is enough that it makes it valuable to players, but not enough that it forces players to run the arcade for the single recipe.
Since everyone complains how easy it is to get recipes from HoH compared to Basil, and the amount of Basil's conflicting recipes. Would be an interesting change.