Kind of surprised how high everyone has Ebron to be honest.
I think he's going about where he should go in my drafts. Usually between 3-6.
As others mentioned, it's pretty special for a TE to get picked in the top 10. More rare than finding a top 5 WR (Watkins), a top 5 QB (Bortles), or a top 10 WR (Evans). There's a decent argument that, relative to his position, Ebron is the best skill prospect in this draft. Vernon Davis is the only other TE to go that high in the past decade (Winslow also went top 10 in 2004). Meanwhile we've seen numerous top 10 QBs and WRs in the same time period. It's a pretty good bet that there will be 1-2 more of those next year whereas we might not see another top 10 TE for 5+ years (though I guess OJ Howard might make a case for himself over the next 2 years).
Point being, he's a pretty elite TE prospect. That's one major variable. There are a few other things that factor into the decision. Watkins and Evans both fit the generic mold of an elite FF WR1 since they both have good size, but Beckham and Cooks do not. There basically aren't any elite NFL WRs in the NFL with their dimensions. I guess you could argue Percy Harvin and Steve Smith. If you look at the best WRs of the past 5-10 years, the list is dominated by big and strong targets (Fitz, Andre, Calvin, Dez, Demaryius, Marshall, VJax, Roddy, Julio, Gordon?, Jeffery?). Strength seems to be a big contributing factor to elite level success. When you take that away, the player in question now has one less way that he can win against defensive backs. So I think there's a legitimate question of whether or not Beckham and Cooks are serious candidates for eventual top 10 dynasty WR status. I think Beckham is a high floor, low ceiling guy who's a near 100% bet to become a solid FF WR2-WR3 and nothing more. Cooks seems to have more upside because his speed/suddenness are at a more elite level and because he's in such a friendly system, but he's a 5'9" squirt who could easily underwhelm like Tavon Austin (who may yet become great but didn't really dominate on offense as a rookie). Add it all up and it makes sense for Watkins and Evans to go ahead of Ebron in every standard PPR league (which they have), but it also makes sense to question whether or not Cooks and Beckham deserve the same. I think they're less likely to become elite at their position, though there's a good argument in a lot of formats that a mid level WR2 is worth more than a mere mortal (i.e. not Jimmy Graham or Tony Gonzalez) TE1.
The RBs don't really change the equation much because there aren't any elite RB prospects in this draft and the 2nd-3rd round guys aren't obvious favorites to start on day one besides Sankey and possibly Mason. So not only are these guys mediocre talents like most of last year's crew, but they won't benefit from the favorable situations that helped boost Zac Stacy, Bishop Sankey, Gio Bernard, and Eddie Lacy into day 1 relevance.
I personally have Ebron ranked as the #3 rookie in this class for a typical PPR league with no TE premium. It's definitely a questionable pick from an upside standpoint because we know that a good WR or RB will usually hold more functional and market value than an equivalent (or even better) TE. At the same time, I don't think Beckham profiles as an elite FF asset and I don't quite like Cooks enough to take him that high (though I think he has a good case for going #3). There's also the issue of scarcity. Why take a future FF WR2-WR3 in the top 5 of the rookie draft when this WR class is so deep with guys who seem to have a good chance at that type of career (i.e. Latimer, Robinson, Adams, etc)? Sankey would be a consideration if I believed in his talent. I think he's a good pick for short-sighted owners looking to turn a quick profit and/or flip their pick quickly, but he's a pedestrian prospect and there will be several guys of his ability entering the league every year. So for me he's not an exciting choice in the top 5. I could see a good argument for Ebron dropping down to 4 or 5, but anything beyond that seems questionable to me. If you're looking for players who have the chance to become true standouts and not just solid complementary pieces, I think he's one of the more high-certainty picks available.