Initial state

No sets defined, hitting compare button activates sets by defining set 1 with currently set filters and adding a 2nd step with no filters applied.

Next state below 👇

Sets activated

Now as sets are activated, the visual presentation changes. Each set sits on a separate row with controls aligned on each side. I positioned the "Remove" action on the far right to avoid mis-clicks with duplicate action. It'd really suck if someone accidentally removed a set with complex filters defined (undo action would help though).

One more interaction below this mock 👇

Duplicate

Lil tooltip appears and the IconButton gets hover state. Newly duplicated set would appear as last, i.e. Set 3 to avoid re-labelling existing sets.