I'm glad you're able to assess the effectiveness of a trade before a guy even touches the ice.
What scoring wingers would be better than Brown, Toffoli, Pearson, Iafallo, Gaborik? I think you're 1. either greatly overestimating the impact of said forwards; 2. overestimating the availability of those forwards. Guys that scored the top end of that 15-18 goal range last year? Landeskog, Athanasiou, Palat, Mantha, Backes, Larkin, etc....which one of those guys is available, and at what cost? You know who else is in that range over the last couple of years? Just about every winger on the top-9 of this team, with Trevor Lewis on the borderline. Edit: also, 'lateral trade' target Jussi Jokinen.
"scoring winger" is literally just about the least of our concerns imo , and those dumpster dive trades you're referring to have actually fulfilled the need you're professing we have--so you either need to be more specific in what you're looking for and how to get it (by raising what you're asking for and consequently what's going out), or admit we already have it.
Frankly I don't think the scoring is a personnel problem aside from the Carter injury (that's a huge one, obviously). It's a performance problem, one that's not going to be solved from the outside minus an unforeseen blockbuster and even then...