I do sets. After finishing my Topps sets I started to do known and unknown variations or variants to the sets. Some refer to such sets as "master" sets. I think most folks feel the sets are complete without the variations.
I know some collectors who strive to get each card in a set that thet are working on autographed. I have never gotten into autographs, but my preference would be to have an autographed set or a regular set, but not mixed, but agree with Tom that whatever pleases you is all that counts
Is this card necessary to have a complete Topps 1984 set ?