Douglas would be helped by Harrison, as teams would double Harrison leaving others 1 on 1. Juju and Thornton are already played 1 on 1 and lose the battle so not sure how Harrison would help them.
With Harrison you need a QB that can throw outside the numbers with some velocity to maximize his ability or teams just double and skew towards the middle against him. Not sure the QB is on the roster that can do that.
QB's always go top 1 or 2 or are over drafted on round 1. The value is to grab one while you are in the top few picks.
Wide receivers you can get lower in round 1 or in round 2, so get the QB year 1, draft the WR later in draft or first round the next year.
Only 2 of the top 15 receivers by yards this year were top 10 picks. Sweet spot is mid first to end of second round.