At the TE position, I think they're in a bit of a bind with Henry that makes finding the right TE2 kind of tough. Might have to be by committee. He's not a road grader blocker as the traditional Y TE, but he's also not really a move guy that really stresses coverages either. I think part of the issue they had with getting guys open was they played so much with Hooper and Henry together and they're kind of the same guy there. It's just kind of clunky. Henry isn't a bad blocker as the Y, but he's just not a road grader and nor is Hooper so you're kind of stuck in no man's land. A little clunky in the passing game without strong benefit in the run game.
That's why Gronk and Hernandez were so dominant.... besides just being good they were also very complimentary. 2 TE offense doesn't really work as a base formation unless it's the right kind of 2 TEs.
I think if they're going to run 2 TE sets a lot then the second guy they pair with Henry needs to be a real move option. Someone like Otton or Goedert, while good players, would be too clunky with Henry. Those are guys you would sign to play in place of Henry. Guys like Pitts/Likely/Okonkwo actually compliment Henry. In those formations, you'll have the ability to challenge the defenses more because the route trees are different. And then you just have to live with Henry as the Y only being an ok, not great blocker.
That's where it makes sense to have a third TE on the roster who is your more traditional road grading blocker. Then if you want to go with the "bigger" 2 TE sets alongside Henry you can do that.
I think my preference would be to sign someone for the move TE role alongside Henry as more of a base formation and then draft a guy who's a more traditional in-line Y who can start out as a blocking specialist in bigger 2 TE sets, but be groomed to eventually replace Henry as more of an every down Y, even you're trading some receiving for blocking there.