Depends on what is considered solid or spectacular. Steve Johnson,mike Williams,Jeremy maclin,Riley cooper,Emanuel sanders,Greg Jennings,Bowe are solid with some of them possible potential to be spectacular.
I'm not really sure what you're saying here so forgive me if this post is a bit all over the map. Is it regarding the 2nd round pick for a solid vet or is it the value of free agency? Because the examples you give are really confusing.
Stevie Johnson was traded for a 4th which can conditionally become a 3rd. Mike Williams was traded for a 6th. No way either of those guys would garner a 2nd-round pick so not sure why they were introduced into the conversation. Sure, trading picks for players can be good (Aqib Talib) and it can be bad (Ochocinco). It's still a risk.
And I think it's important to agree on value. I don't consider $5M a year for a receiver who hasn't caught 50 passes to be great value. $5M is what a top of the 1st-round WR could be expected to receive, not just a solid guy. Riley Cooper is being paid pretty decent cash after signing a 5 year, $22.5M deal while catching 47 passes last season with DeSean Jackson around. That's more than Brandon Lloyd signed with us, and we cut him after catching 27 more passes than Cooper. I don't really see Cooper as great value.
Sanders also couldn't exceed Lloyd's season with the Patriots but is being paid an average of $5M a year on a 3-year deal, twice as much as the offer sheet he signed with the Patriots the year before. Obviously he has significantly more leverage as an unrestricted free agent than before as a restricted free agent, and I expect his numbers will go up playing with Peyton, but I'm not sure if that's a great deal or not. Maclin was injured which affected his market value.
And I really have no idea why you brought up Jennings, who signed a huge 5-year, $47.5M deal and didn't even finish in the top 40 in receiving yards, and had one of his worst seasons after signing the deal. And I'm really confused why you brought up Dwayne Bowe, who also had one of his worst seasons after his big deal (worst if you don't count the season cut short by injuries). He is one of the top 3 paid receivers after his 5-year, $56M deal...he damn well BETTER be more than "possible potential to be spectacular."
I'm not disagreeing that there are good deals in trades and free agency, but there are risks that go with it. If you go high-end, you are generally either overpaying or taking on some type of character/injury risk. Or you're at the low-end bargain-hunting, which can be great, but those are flyers, low-risk/high-reward that you can't depend on. There are exceptions due to circumstances, like system changes or injuries or character concerns.
But there is no fool-proof method of acquiring talent. You need to mix from all of them, but in terms of generating value, the easiest method is the draft.