If I'm not mistaken,
the process to delete one's own set is :
click or tap on "modify set",
then on each cursor high-lighted in green
to remove 'em, & conclude with the "modify" button...
IF I'm not mistaken ...

if I AM mistaken & the platform doesn't allow that, well...
one can alternatively give the set a complete makeover,
by removing the previous cursors, adding new ones,
changing the name, description, & tags accordingly
(typing of the latter... you seem to have
twice the amount of permitted tags ;Þ).
The only draw-backs would be
the identifier(archive's naming) remaining the previous one,
& the left-over comments from the set's previous stage.