First of for taxes
-Allow separate taxes for groups of pokemon, examples are shiny, legends, hidden ability. What this means is there can be separate taxes placed on those groups. If player A wants to list shiny magikarp, he gets taxed 20% of what he listed, while the normal tax for a normal pokemon is 10%. For a hidden ability, it could be 15%, each group is determined in the config. Can be enabled or disabled.
Second off for minimum prices
-Allow a minimum price feature, optional in config. If this is set, it would work how the taxes idea works. Based off of a general group of pokemon, then has the option to go more in depth with shiny, legends, hidden ability. If player A lists a magikarp, they must list it for 1k or more. If it were shiny then the minimum price jumps up to 10k, if there was a legend, maybe 20k (these are examples, amount would be based off of config settings).
Something to keep in mind about, shiny legends. If there could be a section for tax and minimum price for that as well then that would be appreciated.
I ask for these to be included in GTS for economy matters. Can help servers who want a strict economy focus on the pokemon market a bit more.