change elytra price to $15.000, its too good for only 6k
add heavy core for $7.500
add breeze rod for $125
add firework rocket for $25 next to the elytra
add enchanted books that cant be collected through enchantment table (soul speed, swift sneak, wind burst etc.)
fix potion shop having 2-3 of the same potion for the same price (make it better pots for better prices or something if you like ong made it specifically like that)