Now that so many heroes have come out, I find it even more baffling that this is the only threat removal card in Spider-Man's deck. The threat/ER ratio is 1.5, which would have been good... if only it weren't conditional. The immediate comparison is Chase Them Down, which offers a hefty threat/ER ratio of 2 basically at the same conditions (of course there are hidden factors, like the fact that Spider-Tracer is an attachment so it offers more flexibility, but still I don't think it's worth the lower ratio).
All in all, I think this card is quite mediocre and depends too much on the presence of minions. What's even worse is that this card alone makes Spider-Man almost unplayable in Solo with aspects other than Justice, unless against minion-heavy encounter decks, which is honestly quite a shame.
I tend to house-rule that this card is still an upgrade but it doesn't need to be attached to a minion. Instead, the text reads as "Action: Discard this card --> remove 2 threat from a scheme." I find it much more enjoyable and flexible, and it makes Spider-Man more playable with different aspects.