In skyblock i would like to add more stuff to the market place because there is only a limited items in the market place. You should also add Member+ like in creative so they could get a rank for free. I have many ideas in my head but i will tell you guys soon :)
/seen- to see a player last login to the server
/top- goes top of the block you are in
/recipe- tells you the recipe
/friends- friend commands
*+*Also add more space to build things because normally people's plot get squashed*+*