I'd disagree for the following reasons:
1. You're cherry picking. Trumbo and Fowler worked out great, but there's a list of OFers who didn't provide value (Austin Jackson, Parra, Span, Aoki)
2. Dickerson isn't an impact outfielder. He's f***ing s***.
3. I can gather a list of discount pitchers who provided great returns last year (Colon, Hill, Lewis, Estrada, Happ) - just like you can point to a couple of OFers who had great years.
4. Decent OFers like Justin Upton, Span, Rasmus and Parra all cost quite a bit (and subsequently, all of them sucked penis).
The reality is there are SPing and OF bargins available every year and there are SPers and OFers who get overpaid every year. The key is identifying them. This team only has 1 starting OFer right now (who can't hit) and there are no in-house replacements in sight (unless you still believe in Pompey). Adding a young OFer with years of control would be a massive plus for this contending team....Google Cubs, Chicago and see how they built a sustainable winner.
I'd also argue the Blue Jays didn't get "the new Happ". He's remarkably similar to the "old" Happ actually. Only in July and August last year did Happ resemble the "new Happ" that we saw in Pittsburgh the year before. Unless the Jays have identified what he has to do to be that guy consistently (and seeing how he pitching in September & October - there's nothing to suggest they did) - this will be the peak of his value.