There should be a tab for command block and function creations. With the release of 1.12, I think command creations will start to get more popular. However I think it's hard for command blockers to get their work out there because there's nowhere to reliably submit these creations. There's no place where people can specifically look for command mods (correct me if I'm wrong).

Maybe there just aren't enough command blockers around to justify a new tab, but I thought it was worth suggesting.