Well, the tricky thing for me is that I always considered late firsts #25-30 to just be early 2nd round picks and vice versa where #31-#35 were late firsts.
Trading 2nd round picks has been the Leafs Achilles heel for years now. Well, until the introduction of the Shanahan management team.
2nd's hold value because you still have an opportunity to draft one of the top 60 prospects in the world, so teams like to acquire that, and on the other side 2nd round picks are not as valuable as 1st round picks and so teams are more willing to offer them in trades to sweeten the pot enough to get a deal done.