The situation has changed in MLB. With so much parity, and some teams going from last to first and first to last nearly every year, hardly any teams can be considered in total "rebuild mode". Maybe a team like the Braves might be considered a team looking 3 years away, but even they were a 90 win team in 2012 and 2013. Plus, they were trading prospects away in some deals last winter.
No doubt, it's hard to pry a quality young pitcher from any team these days with just a group of prospects, but teams today are also valuing young talent more and more as richer teams are facing tougher and tougher rules on drafting, international signings and more.
I'm done complaining about the Kimbrel trade, but I am totally convinced that a package like the one listed below could have gotten us a very fine pitcher under team control for 3 or more years at a reasonable financial cost.
(Not all oif these guys, but depending on who we are asking for 6 or 7.)
Holt
Swihart
Devers
Guerra
Margot
Asuage
Logan
and one or two from Owens, Johnson and Kopech
The other alternative was to try for a deal where we take on salary from a team looking to dump a player(s). An example might have been Jamie Shields with M Upton or Kemp, or maybe trading for Verlander (not off to a good start so far). Even these types of deals are hard to find.
The best options seem to be for someone like Sonny Gray or Jose Fernandez.
Names like Quintana, Carrasco, Salazar and Kluber were floated around last winter, but it's hard to know much those rumors were real.
We may have tried very hard to find a deal for an ace, but I doubt we offered Swihart and Devers plus more.
I was very much against trying to get Cole Hamels, because he was getting paid near FA money, and Philly wanted too much, but never the less, he was traded away, so it can and does happen.